Four agents audited the code as it is at 14a22c4, each in one area, and a judge reproduced, merged and ranked what they found, then read the code once more itself. Nothing in the code was changed or deployed.

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5 low3 info

• 1.low_build reverts with TickLiquidityOverflow instead of the documented no-op when the wall target is clamped to the floor of the tick rangesrc/DrawdownBurnStrategy.sol:581

          if (raw == 0 || raw > type(uint128).max) return;

  Merged from audit_economics, audit_math and audit_flow (same mechanism, same fix). The round-2 fix clamps wallTarget() to the usable tick range and says a liquidity that does not fit is 'nothing, rather than a revert', but the guard only checks raw > type(uint128).max. Uniswap v4's Pool.modifyLiquidity enforces a far tighter bound, tickSpacingToMaxLiquidityPerTick(tickSpacing) = type(uint128).max / numTicks, about 1.15e34 for spacing 60.

  At the clamped floor range (lower = -887220, upper = -887220 + wallWidth) the sqrt-price difference is only ~1.3e8 (X96), so raw = pending * 2^96 / 1.3e8 ~ pending * 6e21.

  For any pending reserve roughly between 1.9e12 wei and 5.6e17 wei (up to ~0.56 ARB for width 600) raw passes the uint128 check and PoolManager.modifyLiquidity reverts with TickLiquidityOverflow(-887220), so the permissionless buildWall() and the owner's moveWall() revert for everyone until the next hour close lifts the ATH back to the market cap.

  Below ~1.9e12 wei a dust wall is actually laid at the floor; wallTarget() then returns that wall (the price can never cross below MIN_TICK), so every later buildWall tries to add to it and hits the same band, pinning pendingWall until the owner calls moveWall. Precondition is owner-only (lowerAth to a dust value is accepted, the only checks being mcap < athMcap and mcap != 0), so the bank is not at risk and the impact is a temporary, self-inflicted DoS of the wall path.

  Fix: after computing the liquidity also return when uint256(w.liquidity) + raw > Pool.tickSpacingToMaxLiquidityPerTick(tickSpacing) (import Pool from v4-core/src/libraries/Pool.sol), and/or floor lowerAth at a sane fraction of the current market cap.

  whole finding

  Harness: real PoolManager, FeeHook (330 bps) at a mined hook address, Token 1e27 as currency0, MockERC20 reserve as currency1, spacing 60, pool initialized at tick 0 with full-range-ish liquidity 1e24 on [-6000, 6000]; strategy wallWidth 600, maxPerBuy 1e21, athMcap_ 0 (so ATH = mcap at tick 0); vault handed over and activated by a first buildWall() in a new block, pendingWall() == 0.

  Input: mint 1e15 wei of reserve to the vault and vault.sync (as the hook delivers a fee), roll one block, owner calls lowerAth(1): pendingWall() == 1e15 (tier 0), wall.liquidity == 0, wallTarget() == (-887220, -886620).

  Anyone calls buildWall().

  Expected per the comment at lines 577-578: returns, pendingWall stays 1e15, no wall laid.

  Actual: reverts with TickLiquidityOverflow(-887220) from PoolManager.modifyLiquidity, because raw = 1e15 * 2^96 / 1.311e8 ~ 6.04e35 <= uint128.max passes the guard but exceeds maxLiquidityPerTick(60) ~ 1.151e34.

  Ran the attached proof on this tree: '[FAIL: TickLiquidityOverflow(-887220)] test_buildWallDoesNotRevertAtFloorRange()'. audit_flow additionally reports that with pendingWall = 1e12 a dust wall of liquidity 6.04e32 is laid at [-887220, -886620] and with 1e18 the call is the intended no-op, which brackets the band.

  whole reproduction
  proof · a Foundry test that fails on this code and passes once it is fixed

  // SPDX-License-Identifier: MIT
  pragma solidity 0.8.26;
  
  import {Test} from "forge-std/Test.sol";
  import {PoolManager} from "v4-core/src/PoolManager.sol";
  import {IHooks} from "v4-core/src/interfaces/IHooks.sol";
  import {Hooks} from "v4-core/src/libraries/Hooks.sol";
  import {PoolKey} from "v4-core/src/types/PoolKey.sol";
  import {Currency} from "v4-core/src/types/Currency.sol";
  import {TickMath} from "v4-core/src/libraries/TickMath.sol";
  import {ModifyLiquidityParams} from "v4-core/src/types/PoolOperation.sol";
  import {PoolModifyLiquidityTest} from "v4-core/src/test/PoolModifyLiquidityTest.sol";
  import {MockERC20} from "solmate/src/test/utils/mocks/MockERC20.sol";
  
  import {DrawdownBurnStrategy} from "src/DrawdownBurnStrategy.sol";
  import {FeeVault} from "src/FeeVault.sol";
  import {FeeHook} from "src/FeeHook.sol";
  import {Token} from "src/Token.sol";
  import {IFeeStrategy} from "src/interfaces/IFeeStrategy.sol";
  
  /// _build() promises "nothing, rather than a revert" for a wall range it cannot lay, but it only
  /// guards `raw > type(uint128).max`. Uniswap v4 caps liquidity per tick at
  /// type(uint128).max / numTicks (~1.15e34 for spacing 60). With the wall target clamped to the
  /// lowest usable range (an ATH lowered to dust), 0.001 ARB of pending reserve computes to
  /// ~6.04e35 liquidity: under uint128.max, over the per-tick cap, so buildWall() reverts with
  /// TickLiquidityOverflow. Fixed when _build returns instead of calling modifyLiquidity there.
  contract WallFloorProofTest is Test {
      PoolManager pm;
      FeeVault vault;
      Token token;
      MockERC20 reserve;
      DrawdownBurnStrategy strat;
      PoolModifyLiquidityTest lp;
      PoolKey key;
      address owner = address(0xA11CE);
  
      function setUp() public {
          pm = new PoolManager(address(this));
          vault = new FeeVault(address(this));
          address reserveAddr = address(uint160(type(uint160).max) - 0xFFFF);
          deployCodeTo("MockERC20.sol:MockERC20", abi.encode("ARB", "ARB", uint8(18)), reserveAddr);
          reserve = MockERC20(reserveAddr);
          token = new Token("T", "T", 1e27, address(this));
          require(address(token) < reserveAddr, "order");
  
          address hookAddr = address(
              uint160(uint256(keccak256("hook")) & ~uint256(0x3FFF))
                  | uint160(Hooks.AFTER_SWAP_FLAG | Hooks.AFTER_SWAP_RETURNS_DELTA_FLAG)
          );
          deployCodeTo("FeeHook.sol:FeeHook", abi.encode(pm, address(vault), reserveAddr, uint256(330), owner), hookAddr);
  
          key = PoolKey({
              currency0: Currency.wrap(address(token)),
              currency1: Currency.wrap(reserveAddr),
              fee: 3000,
              tickSpacing: 60,
              hooks: IHooks(hookAddr)
          });
          pm.initialize(key, TickMath.getSqrtPriceAtTick(0));
  
          lp = new PoolModifyLiquidityTest(pm);
          reserve.mint(address(this), 1e30);
          token.approve(address(lp), type(uint256).max);
          reserve.approve(address(lp), type(uint256).max);
          lp.modifyLiquidity(key, ModifyLiquidityParams(-6000, 6000, 1e24, 0), "");
  
          address[] memory ex = new address[](0);
          strat = new DrawdownBurnStrategy(pm, vault, key, token, reserveAddr, 0, ex, 1e21, 600, owner);
          vault.setStrategy(IFeeStrategy(address(strat)));
          vault.transferOwnership(address(strat));
          reserve.mint(address(vault), 100e18); // the bank
          vm.roll(block.number + 1);
          strat.buildWall(); // first reading after handover: activates and counts the bank
          assertEq(strat.pendingWall(), 0);
      }
  
      function test_buildWallDoesNotRevertAtFloorRange() public {
          // 0.001 ARB of fee arrives, as the hook delivers it: transfer then sync.
          reserve.mint(address(vault), 1e15);
          vault.sync(address(reserve));
          vm.roll(block.number + 1);
  
          vm.prank(owner);
          strat.lowerAth(1); // observes first: the fee is split (tier 0, all to the wall), then the ATH is floored
          assertEq(strat.pendingWall(), 1e15);
          (,, uint128 liq) = strat.wall();
          assertEq(liq, 0);
  
          (int24 lower, int24 upper) = strat.wallTarget();
          assertEq(lower, -887220); // clamped to the lowest usable tick: correct
          assertEq(upper, -887220 + 600);
  
          // Documented as a no-op. Actual: reverts with TickLiquidityOverflow(-887220).
          strat.buildWall();
  
          // Once it does not revert, the pending reserve must still be intact and no wall laid.
          assertEq(strat.pendingWall(), 1e15);
          (,, liq) = strat.wall();
          assertEq(liq, 0);
          assertEq(reserve.balanceOf(address(vault)), 100e18 + 1e15);
      }
  }

  whole proof

• 2.lowlowerAth lowers athMcap and caps lastMcap but leaves the block's anchored tier: fees for the rest of the L1 block split at the old tiersrc/DrawdownBurnStrategy.sol:715

          athMcap = mcap;

  Merged from audit_economics and audit_permissions (same mechanism, same fix). _observe writes anchor.burnBps once per L1 block from _tierBps(mcap, ath) (lines 437-439). lowerAth calls _observe first, which anchors the block and stores the tier for the OLD ATH, then lowers athMcap and caps lastMcap but never recomputes anchor.burnBps.

  Every fee that arrives in the remainder of that L1 block (about 12 s on Arbitrum, many L2 blocks and swaps) is split at line 474 by the stale, higher tier: more into the pot (spent on buybacks 'whatever the tier later reads') and less into the wall than the ATH the owner just set implies, and currentBurnBps() disagrees with wallTarget(), which already uses the new ATH. Bounded to one L1 block of fees and only moves reserve between pot and pendingWall, never the bank.

  Fix: after lowering, write anchor.burnBps = uint16(_tierBps(lastMcap, mcap)) (lastMcap is the block's anchored reading once capped).

  whole finding

  Hookless v4 pool (spacing 60) initialized at tick -69000, Token 1e27 as currency0, MockERC20 as currency1.

  Deploy a probe strategy with athMcap_ = 0 to read mcap = lastMcap(), then the strategy under test with athMcap_ = 2 * mcap (50% under the ATH).

  Roll one block and warp 13 s: currentBurnBps() == 7500.

  Owner calls lowerAth(mcap * 11 / 10).

  Expected: athMcap == mcap*11/10 (holds) and this block's tier is 2500, since tierBps(lastMcap(), athMcap()) == 2500 (holds).

  Actual: currentBurnBps() still returns 7500 for the rest of the block, and a fee arriving now is split 75% to the pot.

  Ran the attached proof on this tree: '[FAIL: the block's anchored tier must follow the lowered ATH: 7500 != 2500] test_lowerAthUpdatesTheBlocksTier()'.

  whole reproduction
  proof · a Foundry test that fails on this code and passes once it is fixed

  // SPDX-License-Identifier: MIT
  pragma solidity 0.8.26;
  
  import {Test} from "forge-std/Test.sol";
  import {PoolManager} from "v4-core/src/PoolManager.sol";
  import {IPoolManager} from "v4-core/src/interfaces/IPoolManager.sol";
  import {IHooks} from "v4-core/src/interfaces/IHooks.sol";
  import {PoolKey} from "v4-core/src/types/PoolKey.sol";
  import {Currency} from "v4-core/src/types/Currency.sol";
  import {TickMath} from "v4-core/src/libraries/TickMath.sol";
  import {MockERC20} from "solmate/src/test/utils/mocks/MockERC20.sol";
  import {FeeVault} from "src/FeeVault.sol";
  import {Token} from "src/Token.sol";
  import {DrawdownBurnStrategy} from "src/DrawdownBurnStrategy.sol";
  
  /// lowerAth lowers athMcap and caps lastMcap but leaves the block's anchored tier (anchor.burnBps)
  /// at the value computed for the old ATH, so fees arriving in the rest of the L1 block are split
  /// by the stale tier and currentBurnBps() disagrees with the ATH the owner just set.
  contract LowerAthTierTest is Test {
      PoolManager pm;
      MockERC20 arb;
      Token token;
      FeeVault vault;
      PoolKey key;
  
      function setUp() public {
          pm = new PoolManager(address(this));
          arb = new MockERC20("ARB", "ARB", 18);
          for (uint256 i = 0; i < 64; i++) {
              Token t = new Token{salt: bytes32(i)}("T", "T", 1e27, address(this));
              if (address(t) < address(arb)) {
                  token = t;
                  break;
              }
          }
          require(address(token) != address(0), "ordering");
          vault = new FeeVault(address(this));
          // No hook is needed to read the tier: the pool only has to exist at a price.
          key = PoolKey({
              currency0: Currency.wrap(address(token)),
              currency1: Currency.wrap(address(arb)),
              fee: 3000,
              tickSpacing: 60,
              hooks: IHooks(address(0))
          });
          pm.initialize(key, TickMath.getSqrtPriceAtTick(-69000));
      }
  
      function test_lowerAthUpdatesTheBlocksTier() public {
          address[] memory ex = new address[](0);
          // Deploy with the ATH at twice the market cap: 50% under it, tier 7500.
          DrawdownBurnStrategy probe = new DrawdownBurnStrategy(
              IPoolManager(address(pm)), vault, key, token, address(arb), 0, ex, 1e21, 600, address(this)
          );
          uint256 mcap = probe.lastMcap();
          DrawdownBurnStrategy strat = new DrawdownBurnStrategy(
              IPoolManager(address(pm)), vault, key, token, address(arb), mcap * 2, ex, 1e21, 600, address(this)
          );
          vm.roll(block.number + 1);
          vm.warp(block.timestamp + 13);
          assertEq(strat.currentBurnBps(), 7500, "50% under the ATH");
  
          // The owner lowers the ATH to 10% above the market cap: the tier for this block should be 2500.
          strat.lowerAth(mcap * 11 / 10);
          assertEq(strat.athMcap(), mcap * 11 / 10);
          assertEq(strat.tierBps(strat.lastMcap(), strat.athMcap()), 2500, "the tier the new ATH implies");
          assertEq(strat.currentBurnBps(), 2500, "the block's anchored tier must follow the lowered ATH");
      }
  }

  whole proof

• 3.lowAfter releaseVault, moveWall reverts whenever the wall can be re-laid, and burnWall's pot credit silently becomes bank at the next handoversrc/DrawdownBurnStrategy.sol:762

      ///         stays with this contract until {withdrawWall}, {burnWall} or {moveWall}.

  Merged from audit_economics, audit_flow and audit_permissions (same released-state mechanism). releaseVault's natspec (lines 761-762) names withdrawWall, burnWall and moveWall as the ways to get the wall out afterwards, but only withdrawWall behaves as documented once the vault is owned by the EOA. moveWall runs _takeDownWall (reserve back to the vault via poolManager.take + vault.sync, which needs no ownership, _pendingWall += R) and then _build; whenever the price and the anchor are at or above the new target, _build calls _payFromVault (line 591) -> vault.withdraw (line 808), which is onlyOwner on FeeVault, so the whole call reverts with OwnableUnauthorizedAccount(strategy) and the wall cannot be moved while released.

  When the price is under the new target, moveWall 'succeeds' but only parks R as pendingWall, which the next activation resets to 1 (line 464), turning R into bank. burnWall succeeds and sets _pot = 1 + R, but buyback()/buyInside then revert at vault.withdraw and the next activation resets _pot, so R becomes bank instead of being 'bought back and burned, whatever the tier' as lines 721-722 promise.

  The same _payFromVault path makes a permissionless buildWall revert while released once a crossed-wall removal has credited reserve fees to _pendingWall. Conservative for the bank (it can only grow) and no funds are lost (withdrawWall and withdrawFromVault still work), but two of the three documented released-state exits do not do what they say.

  Fix: in _build (or moveWall/burnWall) revert early with a clear error, or return leaving the reserve pending, when vault.owner() != address(this); and document that burnWall's pot credit does not survive a handover.

  whole finding

  Same harness as finding 1 (real PoolManager, FeeHook, Token, MockERC20 reserve, spacing 60, tick 0, strategy active with the vault, 100e18 bank).

  Mint 10e18 of reserve to the vault and sync, roll, buildWall(): a wall is laid at wallTarget() with liquidity > 0 and pendingWall() == 0.

  Owner calls releaseVault(): vault.owner() == owner EOA.

  Roll one block, owner calls moveWall().

  Expected (natspec): the wall is taken down and laid again under the current ATH.

  Actual: revert OwnableUnauthorizedAccount(address(strategy)) from FeeVault.withdraw inside _build -> _payFromVault (test_moveWall_after_release_reverts passes with that expectRevert).

  Second sequence from the same state: owner calls burnWall() instead: it succeeds, pot() > 9e18; buyback() in the next block reverts with OwnableUnauthorizedAccount; the owner then calls vault.transferOwnership(strategy) and anyone calls buyback() in a new block: pot() == 0 and the vault holds 100e18 + the wall's reserve as uncounted bank (test_burnWall_after_release_becomes_bank).

  whole reproduction

• 4.lowwithdrawWall's 'as bank' marking is local to one instance: a successor DrawdownBurnStrategy splits a retired instance's returned wall reserve as a feesrc/DrawdownBurnStrategy.sol:816

          accounted += vault.sync(reserve);

  From audit_flow. _toVault returns reserve to the vault with poolManager.take + vault.sync and bumps this instance's own accounted by the synced amount so its next _observe does not read it as fresh. That marking lives only in the calling instance.

  The documented upgrade path is releaseVault then installing another strategy; if the owner installs a second DrawdownBurnStrategy B and B activates (snapshotting accounted = vault.totalReceived) before the retired instance A has exited its wall, then A.withdrawWall(), documented as returning the reserve 'as bank, never split, spent or laid again', raises vault.totalReceived by the wall's reserve while B.accounted is unchanged, so B's next _observe splits the whole amount into B's pot/pendingWall and B spends it on buybacks or lays it as a wall.

  The same holds for A.burnWall() and A.moveWall(). The pre-handover treasury is not reached: B's bank snapshot excludes it and B only ever spends increases of totalReceived after its activation, so this is a violation of withdrawWall's documented guarantee, not of the top-priority bank invariant.

  Fix options that keep the design: on an instance that no longer owns the vault, have _withdrawWall send the reserve to owner() instead of the vault, or revert and require the wall exits to run before the successor activates; at minimum document that every wall exit on a retired instance must precede the successor's activation.

  whole finding

  Same harness.

  Strategy A active, 10e18 of reserve credited and laid as a wall by buildWall().

  Owner: A.releaseVault(); deploy B = new DrawdownBurnStrategy(same arguments); vault.setStrategy(B); vault.transferOwnership(B); next block B.buyback() (B activates, B.pot() + B.pendingWall() == 0).

  Next block owner calls A.withdrawWall(): vault.totalReceived(reserve) rises by r > 9e18.

  Next block B.buyback().

  Expected per withdrawWall's natspec: the amount is bank and B.pot() + B.pendingWall() stays 0.

  Actual: B.pot() + B.pendingWall() == r (all of it to B's pendingWall at tier 0): test_withdrawWall_counted_as_fee_by_new_strategy asserts exactly this on the current code.

  whole reproduction

• 5.lowConstructor does not check that the pool behind the key is initialized: a mismatched fee/tickSpacing/hooks deploys a strategy anchored at tick 0 with the circulating supply as its ATHsrc/DrawdownBurnStrategy.sol:253

          (, int24 tick,,) = poolManager_.getSlot0(key.toId());

  From audit_permissions. The constructor validates only currency0 == token and currency1 == reserve (lines 231-233); fee, tickSpacing and hooks are stored unchecked. For a key whose pool was never initialized, getSlot0 returns (0, 0, 0, 0): tick 0 is a price of 1 reserve per token, so marketCapAt(0) == circulatingSupply(), which becomes the ATH whenever it exceeds athMcap_.

  Deployment succeeds, the vault can be handed over and activation succeeds (it touches only the vault), every fee is then split at 100% burn (any real market cap is far more than 60% under an ATH of ~1e27) and every poolManager.swap / modifyLiquidity against the stored key reverts with PoolNotInitialized: buyInside fails inside the vault's try/catch on every trade (BuybackSkipped), buyback() and buildWall() with a pending wall revert.

  Recovery is a redeploy plus a second handover. The bank is never spent. Deployment-time input validation, low.

  Fix: read sqrtPriceX96 from getSlot0 and revert PoolMismatch() when it is 0; optionally require key.hooks == the known FeeHook.

  whole finding

  Same harness, live pool at (token, reserve, fee 3000, spacing 60, FeeHook).

  Deploy new DrawdownBurnStrategy(pm, vault, keyWithFee500, token, reserve, 0, [], 1e21, 600, owner) where keyWithFee500 is the same key with fee = 500 (no such pool).

  Expected: the constructor reverts (PoolMismatch).

  Actual: it deploys, athMcap() == circulatingSupply() (1e27, tick 0 read from an empty slot0) and anchor.tick == 0 while the real pool is elsewhere: test_constructor_accepts_uninitialized_pool asserts this on the current code.

  whole reproduction

• 6.infowallTarget() reverts on mulDiv overflow when the circulating supply is tiny but non-zero (level >= circ * 2^64)src/DrawdownBurnStrategy.sol:405

          uint256 sqrtP = circ == 0 ? TickMath.MAX_SQRT_PRICE - 1 : Math.sqrt(FullMath.mulDiv(level, 1 << 192, circ));

  From audit_math. FullMath.mulDiv(level, 1 << 192, circ) reverts when the quotient does not fit 256 bits, i.e. when level >= circ * 2^64.

  The circ == 0 branch is handled and the sqrt price is clamped on both ends afterwards, but the clamp never runs for a circulating supply that is tiny yet non-zero (with an ATH of 1e24, any circ <= ~2.17e4 wei). buildWall and moveWall call wallTarget() via _build, so both revert in that state; burnWall, withdrawWall, buyback and releaseVault are unaffected and the bank is not at risk.

  Reaching it needs almost the entire supply burned or held by the excluded addresses, so it is an edge for completeness.

  Fix: clamp before dividing, e.g. if (circ == 0 || level / circ >= (1 << 64)) sqrtP = TickMath.MAX_SQRT_PRICE - 1; else sqrtP = Math.sqrt(mulDiv(...)).

  Hookless pool at tick 0 for a fresh Token (1e27) against the reserve; the deployer holds all but 1e4 wei, which sit at 0xBEEF; deploy the strategy with excluded_ = [deployer] and athMcap_ = 1e24: circulatingSupply() == 1e4, athMcap() == 1e24.

  Call wallTarget().

  Expected: the price is above MAX_SQRT_PRICE, so the target is clamped to the top usable range (887220 - 600, 887220).

  Actual: level = 4e23 and 4e23 * 2^192 / 1e4 ~ 2^257 overflows, FullMath.mulDiv reverts, and wallTarget()/buildWall()/moveWall() revert.

  After 0xBEEF burns the 1e4 wei (circ == 0) wallTarget() returns (886620, 887220) as intended: test_wallTarget_overflow_tiny_circ asserts both on the current code.

  whole reproduction

• 7.infoHandover order is not enforced: transferring vault ownership to the strategy before setStrategy leaves it inactive, with releaseVault as the only way backsrc/DrawdownBurnStrategy.sol:459

              if (vault.owner() != address(this) || address(vault.strategy()) != address(this)) return;

  From audit_permissions. Activation correctly requires both vault.owner() == this and vault.strategy() == this (the round-2 fix is in place). The strategy exposes no passthrough to FeeVault.setStrategy, so once the vault's ownership has been transferred to the strategy only the strategy could call setStrategy, and it never does.

  If the owner runs the handover as transferOwnership(strategy) then setStrategy(strategy), the second call reverts and the strategy stays inactive: fees keep accruing to the vault as bank and are never split, with no Activated event to show it. Recovery exists (strategy.releaseVault(), then setStrategy, then transferOwnership again) and no funds are at risk, but a deploy script that gets the order wrong fails silently.

  Fix (optional): an onlyOwner claimVault() on the strategy that calls vault.setStrategy(this) when vault.owner() == this, or a note in the README's handover procedure that setStrategy comes first.

  whole finding

  Same harness.

  Owner calls strategy.releaseVault() (vault back to the EOA), deploys B, then calls vault.transferOwnership(B) followed by vault.setStrategy(B).

  Expected: B activates on the next call.

  Actual: setStrategy reverts with OwnableUnauthorizedAccount(owner); in the next block B.buyback() returns at line 459 and B.anchor().active stays false: test_handover_order_not_enforced asserts this on the current code.

• 8.infoDead code: `to` decoded from unlock data is never used (compiler warning), and LiquidityAmounts is imported but unusedsrc/DrawdownBurnStrategy.sol:326

          (uint8 action, address to) = abi.decode(data, (uint8, address));

  From audit_flow. Every unlock caller encodes address(0) as the second word and unlockCallback never reads to; solc warns 'Unused local variable' at 326:24 on every build. The LiquidityAmounts import at line 21 is likewise unused.

  Neither affects behaviour; dropping both silences the warning and shrinks the audited surface. If to is meant for a future recipient-bearing action it must be validated before use.

  forge build on this tree prints 'Warning (2072): Unused local variable. --> src/DrawdownBurnStrategy.sol:326:24'. grep LiquidityAmounts src/DrawdownBurnStrategy.sol matches only the import on line 21.

1. Posted13 minto the first attempt
2. Audit mathAgent #415found 1 low, 1 info

   The review is complete and .imd-findings.json holds two substantiated findings. The source tree is unchanged, and the scratch harness lives only under test/scratch/.

   Treasury invariant (top priority): holds. I traced every path that moves reserve out of the vault. Only _payFromVault spends, and only for amounts bounded by _pot - 1 or _pendingWall - 1. Those counters are credited solely from fees that arrive after activation, or from reserve the wall itself returns. _toVault bumps accounted by exactly what it returns, so returned reserve is never re-split. releaseVault zeroes both counters and the activation flag, and every re-handover re-snapshots accounted and resets them, so nothing counted before a release survives it. A local test that releases and re-hands over the vault confirmed the bank balance and zero counters afterwards.

   Round-2 fixes verified in code and in the harness:

   • releaseVault clears activation and counters, and depends on nothing but storage writes and the vault's ownership transfer.
   • Activation requires both vault.owner() and vault.strategy() to be this contract.
   • lowerAth calls _observe first and caps lastMcap. Note the cap only lasts until the next reading in the same hour, so a pump that is still held re-lifts the ATH at the hour close. That is the documented design, not a defect.
   • In-swap slip is tickSpacing; the standalone path uses 200 ticks.
   • wallTarget clamps to the usable range correctly: with the ATH lowered to 1, it returns lower -887220 and upper -886620 for spacing 60 and width 600.

   Findings:

   • Low, with proof. The "out-of-range liquidity is a no-op" claim does not hold. _build guards only against uint128 overflow, but v4 enforces a per-tick cap of roughly 1.15e34 for spacing 60. At the clamped floor range, 0.001 ARB of pending reserve computes to 6.04e35 liquidity, so buildWall() and moveWall() revert with TickLiquidityOverflow for any pending between roughly 0.00002 and 0.56 ARB. Below that band a dust wall is laid at the floor and pins wallTarget until the owner moves it. Precondition is owner-only (lowerAth to dust) and funds are safe. The proof test fails on this code and passes with a per-tick-cap check added before modifyLiquidity.
   • Info. wallTarget() reverts on mulDiv overflow when circulating supply is non-zero but below level / 2^64. The zero case is handled, the 1 to about 2e4 wei band is not. With a 1M ARB ATH and 1e4 wei circulating, the quotient exceeds 2^256 and buildWall/moveWall revert. Practically unreachable, listed for completeness.

   Not found: no rounding direction that leaks value (wall liquidity rounds down so added never exceeds pending, buyback paid never exceeds the pot), no sign loss in the tick math, no overflow in the tier comparisons or market-cap product at realistic supplies, and no path by which a non-owner can misplace the wall or spend bank.

   ran onclaude · claude-fable-5-1 · 24 turns · 11m 45s · 354 in · 48.4K out · 1.1M cached

   submissionbc67ea323c91c089bdca737040b5b95c20746639fac8272a214a63d008fb6681

   devicef9a12c57a094ca8d32b656994c73e3726e389499d3029a76e3d2aa941e900d16

   started from14a22c460904bf6fa088c13d836833db5689ef9c

   bundlenone

   • low_build reverts with TickLiquidityOverflow instead of the documented no-op when the wall target is clamped to the floor rangesrc/DrawdownBurnStrategy.sol:581

     The round-2 claim is that a wall range at an absurd price (an ATH lowered to nothing) is a no-op: "Past uint128 ... there is no wall to lay: nothing, rather than a revert." The guard only checks raw > type(uint128).max. Uniswap v4's Pool.modifyLiquidity enforces a much tighter bound, tickSpacingToMaxLiquidityPerTick(tickSpacing) = type(uint128).max / numTicks, which is ~1.151e34 for spacing 60.

     At the clamped floor range (lower = -887220, upper = -887220 + wallWidth) the sqrt-price difference is only ~1.31e8 (X96), so liquidity = pending * 2^96 / 1.31e8 ~= pending * 6.04e20.

     For any pending between ~1.9e13 wei and ~5.6e17 wei (0.00002 to 0.56 ARB with wallWidth 600) raw passes the uint128 check and modifyLiquidity reverts with TickLiquidityOverflow(-887220), so buildWall() and moveWall() revert for every caller until the ATH is lifted again by an hour close (up to two clock hours if lowerAth was the hour's last reading).

     Below ~1.9e13 wei a dust wall IS laid at the floor; wallTarget() then returns that wall forever (the price can never cross below MIN_TICK), so every later buildWall tries to add to it and hits the same revert band, pinning pendingWall until the owner calls moveWall.

     The precondition is owner-only (lowerAth to a dust value, or more generally an ATH/circulating ratio whose 40% level prices below MIN_SQRT_PRICE); the bank is not at risk, but the stated no-op guarantee does not hold and the permissionless wall path is bricked for the duration.

     Fix: after computing liquidity, also return when uint256(w.liquidity) + liquidity > Pool.tickSpacingToMaxLiquidityPerTick(tickSpacing) (import Pool from v4-core/src/libraries/Pool.sol), or wrap the modifyLiquidity in a try/catch that leaves pendingWall intact.

     whole finding

     State: strategy active and owning the vault, tier 0 (price at the ATH), pool spacing 60, wallWidth 600, no wall laid.

     Input: a reserve fee of 1e15 wei (0.001 ARB) arrives in the vault; owner calls lowerAth(1) (splits the fee: pendingWall = 1e15, athMcap = 1); anyone calls buildWall().

     Expected: wallTarget() = (-887220, -886620) [verified] and, per the comment at lines 577-578, buildWall returns leaving pendingWall = 1e15 and no wall.

     Actual: raw = 1e15 * 2^96 / 1.311e8 = 6.04e35 <= uint128.max so the guard passes; PoolManager.modifyLiquidity reverts with TickLiquidityOverflow(-887220) because 6.04e35 > maxLiquidityPerTick(60) = 1.151e34; buildWall() and moveWall() revert.

     Proof test test/scratch/WallFloorProof.t.sol fails with exactly that error on this code and passes once _build returns when liquidity exceeds the per-tick cap.

     whole reproduction
     proof · a Foundry test the fix has to pass

     // SPDX-License-Identifier: MIT
     pragma solidity 0.8.26;
     
     import {Test} from "forge-std/Test.sol";
     import {PoolManager} from "v4-core/src/PoolManager.sol";
     import {IHooks} from "v4-core/src/interfaces/IHooks.sol";
     import {Hooks} from "v4-core/src/libraries/Hooks.sol";
     import {PoolKey} from "v4-core/src/types/PoolKey.sol";
     import {Currency} from "v4-core/src/types/Currency.sol";
     import {TickMath} from "v4-core/src/libraries/TickMath.sol";
     import {ModifyLiquidityParams} from "v4-core/src/types/PoolOperation.sol";
     import {PoolModifyLiquidityTest} from "v4-core/src/test/PoolModifyLiquidityTest.sol";
     import {MockERC20} from "solmate/src/test/utils/mocks/MockERC20.sol";
     
     import {DrawdownBurnStrategy} from "src/DrawdownBurnStrategy.sol";
     import {FeeVault} from "src/FeeVault.sol";
     import {FeeHook} from "src/FeeHook.sol";
     import {Token} from "src/Token.sol";
     import {IFeeStrategy} from "src/interfaces/IFeeStrategy.sol";
     
     /// _build() promises "nothing, rather than a revert" for a wall range it cannot lay, but it only
     /// guards `raw > type(uint128).max`. Uniswap v4 caps liquidity per tick at
     /// type(uint128).max / numTicks (~1.15e34 for spacing 60). With the wall target clamped to the
     /// lowest usable range (an ATH lowered to dust), 0.001 ARB of pending reserve computes to
     /// ~6.04e35 liquidity: under uint128.max, over the per-tick cap, so buildWall() reverts with
     /// TickLiquidityOverflow. Fixed when _build returns instead of calling modifyLiquidity there.
     contract WallFloorProofTest is Test {
         PoolManager pm;
         FeeVault vault;
         Token token;
         MockERC20 reserve;
         DrawdownBurnStrategy strat;
         PoolModifyLiquidityTest lp;
         PoolKey key;
         address owner = address(0xA11CE);
     
         function setUp() public {
             pm = new PoolManager(address(this));
             vault = new FeeVault(address(this));
             address reserveAddr = address(uint160(type(uint160).max) - 0xFFFF);
             deployCodeTo("MockERC20.sol:MockERC20", abi.encode("ARB", "ARB", uint8(18)), reserveAddr);
             reserve = MockERC20(reserveAddr);
             token = new Token("T", "T", 1e27, address(this));
             require(address(token) < reserveAddr, "order");
     
             address hookAddr = address(
                 uint160(uint256(keccak256("hook")) & ~uint256(0x3FFF))
                     | uint160(Hooks.AFTER_SWAP_FLAG | Hooks.AFTER_SWAP_RETURNS_DELTA_FLAG)
             );
             deployCodeTo("FeeHook.sol:FeeHook", abi.encode(pm, address(vault), reserveAddr, uint256(330), owner), hookAddr);
     
             key = PoolKey({
                 currency0: Currency.wrap(address(token)),
                 currency1: Currency.wrap(reserveAddr),
                 fee: 3000,
                 tickSpacing: 60,
                 hooks: IHooks(hookAddr)
             });
             pm.initialize(key, TickMath.getSqrtPriceAtTick(0));
     
             lp = new PoolModifyLiquidityTest(pm);
             reserve.mint(address(this), 1e30);
             token.approve(address(lp), type(uint256).max);
             reserve.approve(address(lp), type(uint256).max);
             lp.modifyLiquidity(key, ModifyLiquidityParams(-6000, 6000, 1e24, 0), "");
     
             address[] memory ex = new address[](0);
             strat = new DrawdownBurnStrategy(pm, vault, key, token, reserveAddr, 0, ex, 1e21, 600, owner);
             vault.setStrategy(IFeeStrategy(address(strat)));
             vault.transferOwnership(address(strat));
             reserve.mint(address(vault), 100e18); // the bank
             vm.roll(block.number + 1);
             strat.buildWall(); // first reading after handover: activates and counts the bank
             assertEq(strat.pendingWall(), 0);
         }
     
         function test_buildWallDoesNotRevertAtFloorRange() public {
             // 0.001 ARB of fee arrives, as the hook delivers it: transfer then sync.
             reserve.mint(address(vault), 1e15);
             vault.sync(address(reserve));
             vm.roll(block.number + 1);
     
             vm.prank(owner);
             strat.lowerAth(1); // observes first: the fee is split (tier 0, all to the wall), then the ATH is floored
             assertEq(strat.pendingWall(), 1e15);
             (,, uint128 liq) = strat.wall();
             assertEq(liq, 0);
     
             (int24 lower, int24 upper) = strat.wallTarget();
             assertEq(lower, -887220); // clamped to the lowest usable tick: correct
             assertEq(upper, -887220 + 600);
     
             // Documented as a no-op. Actual: reverts with TickLiquidityOverflow(-887220).
             strat.buildWall();
     
             // Once it does not revert, the pending reserve must still be intact and no wall laid.
             assertEq(strat.pendingWall(), 1e15);
             (,, liq) = strat.wall();
             assertEq(liq, 0);
             assertEq(reserve.balanceOf(address(vault)), 100e18 + 1e15);
         }
     }

     whole proof

   • infowallTarget() reverts on mulDiv overflow when the circulating supply is below level / 2^64 (circ == 0 is handled, 1..~2e4 wei is not)src/DrawdownBurnStrategy.sol:405

     FullMath.mulDiv(level, 1 << 192, circ) reverts when the quotient does not fit in 256 bits, i.e. when level >= circ * 2^64. The circ == 0 branch is handled and the sqrtP result is clamped on both ends afterwards, but the clamp never runs for a circulating supply that is tiny yet non-zero. With a plausible ATH of 1e24 wei (1M ARB) level = 4e23, and any circ <= 2.17e4 wei makes 4e23 * 2^192 / circ >= 2^256.

     Since buildWall and moveWall call wallTarget() via _build, both revert in that state; burnWall, withdrawWall, buyback and releaseVault are unaffected and the bank is not at risk. The state needs almost the entire supply burned or placed at excluded addresses (the owner's setExcluded of up to 8 holders can shrink circ), so it is an edge for completeness rather than a live risk.

     Fix: clamp before the division, e.g. if (circ == 0 || level / circ >= (1 << 64)) sqrtP = MAX_SQRT_PRICE - 1 before calling mulDiv.

     whole finding

     State: athMcap = 1e24, token.totalSupply() - excluded balances - strategy balance = 1e4 wei (e.g. all but 1e4 wei of the supply held by the 8 excluded addresses), wall.liquidity == 0.

     Call wallTarget() (or buildWall()/moveWall()).

     Expected: the price is above MAX_SQRT_PRICE so the target is clamped to the top usable range and _build no-ops.

     Actual: level = 1e24 * 4000 / 10000 = 4e23; 4e23 * 2^192 / 1e4 = 4e19 * 2^192 ~= 2^257.1 > 2^256 - 1, FullMath.mulDiv reverts (overflow), wallTarget(), buildWall() and moveWall() all revert.

     whole reproduction
3. Audit flowAgent #656found 3 low, 1 info

   The review is complete and .imd-findings.json is written and validated. All four snippets match their file lines, and no tracked file was modified.

   Top priority verdict: the bank holds. I traced every path that credits _pot or _pendingWall and every path that pays out of the vault. Counters only grow from increases in the vault's totalReceived after activation, or from reserve the strategy itself returns through _toVault, which bumps accounted by exactly the synced amount. Spending is capped by those counters. I then ran a scratch harness (hookless v4 pool, which the strategy accepts) through fees, buybacks, buildWall, releaseVault, an owner withdrawal while released, burnWall while released, re-handover, more fees and walls, moveWall, withdrawWall, and withdrawFromVault. The vault balance never dropped below the bank snapshot at any step. The round-2 fixes behave as described: release clears activation and counters, re-handover re-snapshots accounted and resets both counters, activation checks both vault.owner() and vault.strategy(), lowerAth observes first and caps lastMcap, and the in-swap slip is one tick spacing.

   Findings written (three low, one info), each verified in the harness:

   • moveWall reverts after releaseVault. The release docs list it as an exit for the wall, but _build pays from the vault via onlyOwner withdraw, so it fails with OwnableUnauthorizedAccount once the vault is handed back. withdrawWall and burnWall still work.
   • Out-of-range wall is not always a no-op. The guard at line 581 checks uint128.max, but v4 reverts above maxLiquidityPerTick (about 1.15e34 for spacing 60). After lowerAth(1), pending between roughly 1.9e12 and 5.6e17 wei makes buildWall and moveWall revert with TickLiquidityOverflow, and smaller pending lays a dust wall at the bottom tick. Owner-induced, self-clearing within an hour.
   • withdrawWall's "as bank" marking does not survive a strategy swap. A replacement instance that activates before the old one exits its wall splits the returned reserve as a fee and can spend it. The pre-handover treasury itself is not reachable this way.
   • Info: unused to decode at line 326 (compiler warning) and an unused LiquidityAmounts import.

   Not covered: the in-swap onFeeReceived path with the real hook was analysed by reading only, since the harness used a hookless pool. The FeeHook's address-mined permissions were not exercised. No proofs were attached because nothing reached high severity.

   ran onclaude · claude-fable-5-1 · 29 turns · 13m 47s · 546 in · 58.9K out · 1.8M cached

   submission76cdd80994b615de01126bd8ab1781f4defb8204cc187fdfb37b85b66185abe6

   device96eeb8eb2acdbbf103098abb0d1b9d8aa4666caeb4c29dfd10f0c62c7de4bd52

   started from14a22c460904bf6fa088c13d836833db5689ef9c

   bundlenone

   • lowmoveWall reverts after releaseVault, although releaseVault's docs list it as a way to take the wall outsrc/DrawdownBurnStrategy.sol:762

     releaseVault() hands the vault back to the owner but leaves the wall with the strategy, and its natspec (lines 761-762) names moveWall as one of the three exits. moveWall runs _takeDownWall() then _build(). _takeDownWall returns the wall's reserve to the vault with _toVault (permissionless sync/take, works) and credits _pendingWall; _build then, whenever the price and anchor are at or above the new target, pays the reserve back out of the vault through _payFromVault -> vault.withdraw(), which is onlyOwner on FeeVault.

     After release the strategy is no longer the vault's owner, so the whole unlock reverts with OwnableUnauthorizedAccount(strategy). Only when the price is under the new target does moveWall 'succeed' (and then it just parks the reserve as pendingWall that the next re-handover converts to bank). No funds are at risk: withdrawWall and burnWall still work after release.

     Fix: either document that moveWall needs the vault (and have it revert early with a clear error when vault.owner() != address(this)), or drop moveWall from releaseVault's list of exits.

     whole finding

     State: strategy active, a wall laid (e.g. 10 ARB pending laid at ~50% drawdown), then owner calls releaseVault().

     Next block owner calls moveWall().

     Expected (per natspec): the wall is taken down and re-laid under the current ATH.

     Actual: revert OwnableUnauthorizedAccount(address(strategy)) from FeeVault.withdraw inside _build -> _payFromVault.

     Verified with a hookless v4 pool harness: test_moveWall_after_release_reverts passes with vm.expectRevert(OwnableUnauthorizedAccount(strat)).

   • low_build's out-of-range guard checks uint128.max, but v4 rejects liquidity above maxLiquidityPerTick: buildWall/moveWall revert instead of no-op after a near-zero lowerAthsrc/DrawdownBurnStrategy.sol:581

     The round-2 fix clamps wallTarget to the usable tick range and treats an out-of-range liquidity as a no-op, with the comment 'Past uint128 ... nothing, rather than a revert.' But PoolManager.modifyLiquidity reverts with Pool.TickLiquidityOverflow when liquidityGross at either tick exceeds tickSpacingToMaxLiquidityPerTick(spacing), which is type(uint128).max / numTicks (~1.15e34 for spacing 60), far below type(uint128).max (~3.4e38).

     When the ATH has been lowered so far that wallTarget clamps to the bottom of the range (lower = -887220, upper = -886620 for width 600), sqrtP(upper)-sqrtP(lower) is ~1.3e8, so raw = pending * 2^96 / 1.3e8 ~ pending * 6e21.

     Three regimes follow for the pending reserve: below ~1.9e12 wei a real (dust) wall is laid at the floor of the tick range; between ~1.9e12 and ~5.6e17 wei _modify reverts TickLiquidityOverflow so buildWall() (permissionless) and moveWall() revert for everyone; only above that is it the documented no-op.

     Preconditions: owner calls lowerAth with a tiny value (lowerAth(1) is accepted since the only checks are mcap < athMcap and mcap != 0). The condition clears itself at the next hour close that lifts the ATH to the current market cap, so the DoS window is at most ~1 hour per such call, and withdrawWall/burnWall are unaffected.

     Fix: compare raw against Pool.tickSpacingToMaxLiquidityPerTick(tickSpacing) (minus the current wall.liquidity when adding to an existing wall) instead of type(uint128).max, and/or floor lowerAth at a sane fraction of the current market cap.

     whole finding

     Hookless v4 pool, spacing 60, wallWidth 600, price tick -69060, strategy active with ATH = current mcap.

     Credit 1e16 wei of reserve to the vault and observe (tier 0 so pendingWall = 1e16).

     Owner calls lowerAth(1); wallTarget() returns (-887220, -886620).

     Next block anyone calls buildWall().

     Expected (code comment and round-2 note): no-op, pending stays.

     Actual: revert Pool.TickLiquidityOverflow(-887220).

     With pendingWall = 1e12 instead, buildWall lays a wall of liquidity 6.04e32 at ticks [-887220, -886620]; with 1e18 it is the no-op.

     Verified: test_lowerAth_buildWall_reverts, test_lowerAth_buildWall_dust_wall, test_lowerAth_buildWall_noop_large all pass against the code as is.

     whole reproduction

   • lowwithdrawWall's 'as bank, counted as no fee' marking is local to one strategy instance: a replacement DrawdownBurnStrategy splits the returned wall reserve as a feesrc/DrawdownBurnStrategy.sol:639

     _toVault returns reserve to the vault via poolManager.take + vault.sync and bumps this contract's own accounted by the synced amount so the next _observe does not see it as fresh. That marking lives only in the calling instance.

     The documented upgrade path is releaseVault -> install another strategy; if the owner installs a second DrawdownBurnStrategy (B) and B activates (snapshotting accounted = vault.totalReceived) before the retired instance (A) is asked to exit its wall, then A.withdrawWall() -- documented as returning the reserve 'as bank, never split, spent or laid again' -- increases vault.totalReceived by the wall's reserve while B.accounted is unchanged, so B's next _observe splits the whole amount into B's pot/pendingWall and B spends it on buybacks or lays it as a wall.

     The same happens for A.burnWall()/A.moveWall() (whose reserve A would have credited to its own, now meaningless, counters). The pre-handover treasury itself is not reached: B's bank snapshot excludes it and B still only spends fresh totalReceived increases.

     Fix options that keep the design: on an instance that no longer owns the vault, have _withdrawWall send the reserve to owner() (or revert and require withdrawWall before the vault is re-handed), or document that all wall exits on a retired instance must run before the successor activates.

     whole finding

     Strategy A active, wall laid with ~10 ARB of pending (price ~50% under ATH).

     Owner: A.releaseVault(); deploy B = new DrawdownBurnStrategy(...); vault.setStrategy(B); vault.transferOwnership(B); next block B.buyback() (B activates, B.pot()+B.pendingWall() == 0).

     Next block owner calls A.withdrawWall(): 9999999999999999999 wei of reserve arrive in the vault.

     Next block B.buyback().

     Expected (natspec of withdrawWall/_withdrawWall): the amount is bank, B.pot()+B.pendingWall() stays 0.

     Actual: B.pendingWall() == 9999999999999999999 (tier 0 in the test), i.e. the wall reserve is now spendable by B.

     Verified with test_withdrawWall_counted_as_fee_by_new_strategy (assertion fails on the current code with 9999999999999999999 != 0).

     whole reproduction

   • infoDead code: `to` decoded from unlock data is never used, and LiquidityAmounts is imported but unusedsrc/DrawdownBurnStrategy.sol:326

     Every unlock caller encodes address(0) as the second word and unlockCallback never reads to (solc warns 'Unused local variable' at 326:24 on every build). The LiquidityAmounts import at line 21 is likewise unused. Neither affects behaviour; removing them silences the compiler warning and shrinks the audited surface.

     If to is meant for a future recipient-bearing action, it should be validated before use, since unlockCallback trusts the data it decodes (only the PoolManager can call it, and only the strategy's own nonReentrant entry points unlock with this contract as callback, so today that is safe).

     forge build on the current tree prints: Warning (2072): Unused local variable. --> src/DrawdownBurnStrategy.sol:326:24. grep for LiquidityAmounts in src/DrawdownBurnStrategy.sol finds only the import on line 21.

4. Audit permissionsAgent #1444found 2 low, 2 info

   The review is complete and .imd-findings.json holds the result. No source files were modified; only the findings file and two scratch tests under test/scratch/ were written.

   Top priority: the bank cannot be spent. I traced every path that moves reserve and then exercised them in a Foundry harness with the real PoolManager, FeeHook, FeeVault and Token. The quantity vault balance − pot − pendingWall stayed exactly equal to the bank across activation, splits, in-swap and standalone buybacks, buildWall, moveWall, burnWall, a crash through the wall with the anchor following and the crossed-wall burn, releaseVault, swaps while released, withdrawWall while released, two re-handovers, and an owner withdrawal. Each re-activation reset pot and pendingWall to zero and re-snapshotted accounted. All six round-2 fixes are present and behave as described at src/DrawdownBurnStrategy.sol:308, :410, :459, :463, :581, :713, and :767.

   Why the bank is safe, in one line each.

   • Counters only grow when the vault's totalReceived grows past accounted, or when the strategy itself returns reserve to the vault and raises accounted by the same amount.
   • Every withdrawal from the vault is bounded by a counter, and withdrawFromVault shrinks the counters whenever the vault no longer covers them.
   • The vault's distribute always reverts through onFees, so the whole-balance handover path is closed.
   • Activation requires both vault.owner and vault.strategy to be this contract, and only releaseVault can clear it.

   Findings written (no critical or high):

   • Low, with proof. lowerAth rewrites athMcap and lastMcap but not the block's anchored burnBps, so fees for the rest of that L1 block split at the old tier and currentBurnBps disagrees with the new ATH. The attached test fails on the current code (7500 instead of 2500).
   • Low. The constructor never checks the pool is initialized. A key with a wrong fee, spacing or hook deploys, sets the ATH from the tick-0 price, and every later pool call reverts.
   • Info. burnWall and moveWall in the released state do not do what their docs say. The reserve ends up as bank at the next handover, or moveWall reverts. Reproduced in the harness.
   • Info. Handover order is not enforced. Transferring the vault before setStrategy leaves the strategy inactive, recoverable only through releaseVault.

   Coverage and limits. The Access Control, Trust Gap and Asymmetry passes covered every state-changing entry point, including the hook callback, the permissionless vault notification, and the unlock callback. One in-swap buyback in the harness hit the 400k cap and was skipped, which is the documented fallback and did not affect accounting. Fork tests against the live pool were not available, and no static analyzer ran.

   ran onclaude · claude-fable-5-1 · 29 turns · 14m 41s · 610 in · 63.1K out · 2.3M cached

   submission68402f987652358b44e460370cad857131c327477558b722c34c53af0124a0cb

   devicec4617da5f1fd5ce8112e5252446ab1d403e6d79885d877f44eb471695a0e5bb8

   started from14a22c460904bf6fa088c13d836833db5689ef9c

   bundlenone

   • lowlowerAth rewrites athMcap and lastMcap but not the block's burnBps: fees for the rest of the L1 block split at the old tiersrc/DrawdownBurnStrategy.sol:715

     Asymmetry between the two writers of the tier. _observe writes athMcap together with anchor.burnBps (computed by _tierBps(mcap, ath) in _anchorNow, lines 437-439 and 451-453). lowerAth calls _observe first, which anchors the current L1 block and stores burnBps for the OLD ath, then lowers athMcap and caps lastMcap, but leaves anchor.burnBps as it was.

     Every fee that arrives in the remainder of that L1 block (about 12 seconds on Arbitrum, many L2 blocks and swaps) is split by the stale tier at line 474 (toPot = fresh * a.burnBps / BPS). The tier is only re-read at the next L1 block.

     The drift is bounded to one L1 block and only moves reserve between the pot and pendingWall (never touches the bank), so this is low; the inconsistency is that lowerAth promises to apply the new ATH, and currentBurnBps() reports the stale value for the rest of the block while wallTarget() already uses the new one.

     whole finding

     State: athMcap = 100e18, anchor for L1 block N already written with burnBps = 7500 (lastMcap = 45e18, 55% under the ATH).

     Owner calls lowerAth(50e18) in block N.

     Expected: athMcap = 50e18 and this block's tier becomes 2500 (45e18 is 10% under 50e18).

     Actual: athMcap = 50e18 but anchor.burnBps stays 7500; a sell fee of 1000e18 ARB arriving later in block N splits 750e18 to pot / 250e18 to pendingWall (Split event) instead of 250e18 / 750e18; currentBurnBps() returns 7500 until block N+1.

     Fix: after lowering, recompute and store anchor.burnBps = uint16(_tierBps(lastMcap, mcap)) (lastMcap is the block's anchored mcap after the cap).

     Reproduced with test/scratch/LowerAthTier.t.sol (attached as proof): deploy with athMcap_ = 2mcap, roll one block, currentBurnBps() == 7500; lowerAth(mcap11/10); tierBps(lastMcap, athMcap) == 2500 but currentBurnBps() still returns 7500 (test fails '7500 != 2500').

     whole reproduction
     proof · a Foundry test the fix has to pass

     // SPDX-License-Identifier: MIT
     pragma solidity 0.8.26;
     
     import {Test} from "forge-std/Test.sol";
     import {PoolManager} from "v4-core/src/PoolManager.sol";
     import {IPoolManager} from "v4-core/src/interfaces/IPoolManager.sol";
     import {IHooks} from "v4-core/src/interfaces/IHooks.sol";
     import {PoolKey} from "v4-core/src/types/PoolKey.sol";
     import {Currency} from "v4-core/src/types/Currency.sol";
     import {TickMath} from "v4-core/src/libraries/TickMath.sol";
     import {MockERC20} from "solmate/src/test/utils/mocks/MockERC20.sol";
     import {FeeVault} from "src/FeeVault.sol";
     import {Token} from "src/Token.sol";
     import {DrawdownBurnStrategy} from "src/DrawdownBurnStrategy.sol";
     
     /// lowerAth lowers athMcap and caps lastMcap but leaves the block's anchored tier (anchor.burnBps)
     /// at the value computed for the old ATH, so fees arriving in the rest of the L1 block are split
     /// by the stale tier and currentBurnBps() disagrees with the ATH the owner just set.
     contract LowerAthTierTest is Test {
         PoolManager pm;
         MockERC20 arb;
         Token token;
         FeeVault vault;
         PoolKey key;
     
         function setUp() public {
             pm = new PoolManager(address(this));
             arb = new MockERC20("ARB", "ARB", 18);
             for (uint256 i = 0; i < 64; i++) {
                 Token t = new Token{salt: bytes32(i)}("T", "T", 1e27, address(this));
                 if (address(t) < address(arb)) {
                     token = t;
                     break;
                 }
             }
             require(address(token) != address(0), "ordering");
             vault = new FeeVault(address(this));
             // No hook is needed to read the tier: the pool only has to exist at a price.
             key = PoolKey({
                 currency0: Currency.wrap(address(token)),
                 currency1: Currency.wrap(address(arb)),
                 fee: 3000,
                 tickSpacing: 60,
                 hooks: IHooks(address(0))
             });
             pm.initialize(key, TickMath.getSqrtPriceAtTick(-69000));
         }
     
         function test_lowerAthUpdatesTheBlocksTier() public {
             address[] memory ex = new address[](0);
             // Deploy with the ATH at twice the market cap: 50% under it, tier 7500.
             DrawdownBurnStrategy probe = new DrawdownBurnStrategy(
                 IPoolManager(address(pm)), vault, key, token, address(arb), 0, ex, 1e21, 600, address(this)
             );
             uint256 mcap = probe.lastMcap();
             DrawdownBurnStrategy strat = new DrawdownBurnStrategy(
                 IPoolManager(address(pm)), vault, key, token, address(arb), mcap * 2, ex, 1e21, 600, address(this)
             );
             vm.roll(block.number + 1);
             vm.warp(block.timestamp + 13);
             assertEq(strat.currentBurnBps(), 7500, "50% under the ATH");
     
             // The owner lowers the ATH to 10% above the market cap: the tier for this block should be 2500.
             strat.lowerAth(mcap * 11 / 10);
             assertEq(strat.athMcap(), mcap * 11 / 10);
             assertEq(strat.tierBps(strat.lastMcap(), strat.athMcap()), 2500, "the tier the new ATH implies");
             assertEq(strat.currentBurnBps(), 2500, "the block's anchored tier must follow the lowered ATH");
         }
     }

     whole proof

   • lowConstructor does not check the pool is initialized: a mismatched PoolKey deploys a strategy whose ATH is the tick-0 market cap and whose every pool call revertssrc/DrawdownBurnStrategy.sol:253

     The constructor validates only currency0 == token and currency1 == reserve (lines 231-233). The fee, tickSpacing and hooks fields of the key are stored unchecked. For a key whose pool was never initialized, getSlot0 returns (0, 0, 0, 0): tick 0 is price 1 ARB per token, so marketCapAt(0) = circulatingSupply (e.g. ~1e27 for a 1e9-token supply), which is taken as the ATH because it exceeds any realistic athMcap_.

     Deployment succeeds, the owner can hand the vault over, activation succeeds (it touches only the vault), fees are split at 100% burn (any real mcap is >60% under a 1e27 ATH), and every swap / modifyLiquidity against the stored key reverts with PoolNotInitialized: buyInside reverts inside the vault's try/catch on every trade (BuybackSkipped), buyback() and buildWall() revert. The misdeploy is detectable only by redeploying and re-handing over the vault. The bank is never spent.

     Deployment-time input validation; low.

     whole finding

     Input: the correct token/reserve but key.fee = 3000 instead of the live pool's fee (or a wrong tickSpacing / hooks).

     Expected: constructor reverts (PoolMismatch).

     Actual: deploys; athMcap == circulatingSupply() * 1 (tick 0), anchor.tick == 0, every later poolManager.swap/modifyLiquidity on _key() reverts PoolNotInitialized.

     Fix: read sqrtPriceX96 from getSlot0 and if (sqrtPriceX96 == 0) revert PoolMismatch(); and, since the hook is immutable per pool, optionally require key.hooks == the known FeeHook.

     whole reproduction

   • infoburnWall / moveWall while the vault is released do not do what their docs say: the wall's reserve becomes bank at the next handover (or moveWall reverts)src/DrawdownBurnStrategy.sol:723

     Only withdrawWall is documented as the released-state wall exit (line 761-762 says the wall stays until withdrawWall, burnWall or moveWall).

     In the released state (anchor.active == false, vault owned by the strategy's owner) the three behave differently. burnWall: _burnWall succeeds (the vault's sync and the pool take need no ownership), puts the reserve in the vault and sets _pot = 1 + r; but buyback()/buyInside then revert at vault.withdraw (not the vault's owner), and the next activation resets _pot to 1 (line 463), so the reserve silently becomes bank instead of being bought back and burned as the NatSpec on line 721-722 promises. moveWall: _takeDownWall succeeds, then _build either (a) reverts at _payFromVault when the price is above the new wall top, reverting the whole call, or (b) returns early, leaving _pendingWall = 1 + r which the next activation also wipes to bank.

     The outcome is conservative for the bank (it can only grow) so this is informational, but the owner is given three owner functions whose effect in the released state is not the documented one and is not reverted.

     whole finding

     State: wall laid with 1000e18 ARB from fees, owner has called releaseVault().

     Owner calls burnWall().

     Expected (per NatSpec): the 1000e18 is bought back and burned at the usual pace.

     Actual: WallSentToBurn emitted, pot() == 1000e18, vault holds +1000e18, but buyback() reverts with OwnableUnauthorizedAccount from the vault; after vault.transferOwnership(strategy) and the next _observe, pot() == 0 and the 1000e18 is uncounted bank.

     Fix: either revert burnWall/moveWall when !anchor.active (keep withdrawWall as the released-state exit), or document that in the released state both are equivalent to withdrawWall.

     Reproduced in a Foundry harness with the real PoolManager, FeeHook, FeeVault and Token (test_burnWallWhileReleasedBecomesBank): after releaseVault(), burnWall() succeeds and pot() == the wall's reserve; buyback() then reverts; after vault.transferOwnership(strategy) and one swap, pot() == 0.

     whole reproduction

   • infoHandover order is not enforced: transferring vault ownership to the strategy before setStrategy(this) leaves it inactive with no way to change the vault's strategy except releaseVaultsrc/DrawdownBurnStrategy.sol:459

     Activation requires both vault.owner() == this and vault.strategy() == this (the round-2 fix is in place and correct). The strategy exposes no passthrough to FeeVault.setStrategy, so once the vault's ownership has been transferred to the strategy, only the strategy can call setStrategy, and it never does.

     If the owner performs the handover in the order transferOwnership(strategy) then setStrategy(strategy), the second call reverts (OwnableUnauthorizedAccount: the vault's owner is now the strategy) and the strategy stays inactive forever; fees keep accruing to the vault as bank and are never split.

     Recovery exists: strategy.releaseVault() hands the vault back, then setStrategy, then transferOwnership again. No funds are at risk, but the launch runbook must fix the order (setStrategy first), and a deploy script that gets it wrong fails silently rather than loudly (onFeeReceived just returns).

     whole finding

     State: vault owned by the EOA owner, vault.strategy() == previous strategy.

     Owner calls vault.transferOwnership(newStrategy) then vault.setStrategy(newStrategy).

     Expected: the strategy activates on the next swap.

     Actual: setStrategy reverts; the next swap's onFeeReceived returns at line 459 with no Activated event; pot()/pendingWall() stay 0 while vault.totalReceived grows.

     Fix (optional): an onlyOwner claimVault() on the strategy that calls vault.setStrategy(this) when vault.owner() == this, or a note in the README handover procedure.

     whole reproduction
5. Audit economicsAgent #1443found 3 low

   Review complete. The findings file holds three verified low-severity defects, and the top-priority bank invariant held under every sequence I could construct.

   Top priority: the treasury bank. I built a Foundry harness under test/scratch/ with a real PoolManager, the project's Token, FeeVault and FeeHook (CREATE2-flag address), a funded 1000 ARB bank in the vault before the strategy existed, and the strategy installed as vault owner and strategy. Randomized 24-call sequences over 512 fuzz runs covered sells, buys, in-swap and external buybacks, buildWall, burnWall, moveWall, withdrawWall, releaseVault followed by re-handover (with and without fees arriving while released), lowerAth, hour rollovers, owner withdrawFromVault, and distribute. In every run the vault balance minus pot minus pendingWall never decreased except through the owner's own withdrawFromVault, pot plus pendingWall never exceeded the vault's balance, and distribute always reverted. An attacker holding their own unlock who dumped the price and called vault.onFeeReceived directly triggered a buyback at the dumped price and left the bank byte-identical. The round-2 fixes all check out: releaseVault resets activation and counters, every handover re-snapshots accounted and resets pot and pendingWall, activation requires both vault.owner and vault.strategy to be the strategy, lowerAth observes first and caps lastMcap, the in-swap slip is one tick spacing, and wallTarget clamps to the usable range.

   Findings written to .imd-findings.json (all low):

   • Wall no-op has a revert band. _build bails only when raw liquidity exceeds uint128, but the pool reverts earlier at maxLiquidityPerTick. With the ATH lowered to 1 and pending of 0.247 ARB, buildWall reverts with TickLiquidityOverflow(-887220) instead of doing nothing. Owner-induced and self-healing at the next hour close.
   • lowerAth leaves the block's tier stale. After lowering the ATH below the market cap, the same L1 block still splits fees at 2500 bps. A sell in that block emitted Split(2500, ...) and credited 0.154 ARB to the pot that should have gone to the wall.
   • moveWall is dead while released. After releaseVault, moveWall reverts whenever the wall could be re-laid, since _build must withdraw from a vault the strategy no longer owns. burnWall while released credits the pot, but that credit is wiped at the next handover and becomes bank. No funds lost, but the documented released-state surface does not match behavior.

   No critical or high findings, so no proof tests are attached. Nothing outside test/scratch/ and the findings file was written, and git status shows the tree clean.

   ran onclaude · claude-fable-5-1 · 32 turns · 18m 10s · 578 in · 71.1K out · 2.1M cached

   submission59e5d9dc3f7a9aef62726892266c4dbd3ad0377d7f8b8b6966f06b6c33dd4c1c

   device62491201fe455e89aed88061fbf0829129b19dcdaa5db7c0351f2076d056da31

   started from14a22c460904bf6fa088c13d836833db5689ef9c

   bundlenone

   • low_build reverts with TickLiquidityOverflow instead of the intended no-op when a lowered ATH puts the wall at the bottom of the tick range and pending is smallsrc/DrawdownBurnStrategy.sol:581

     The round-2 fix makes _build return silently when the computed liquidity does not fit a uint128 ('nothing, rather than a revert'). But the pool manager's real bound is lower: Pool.modifyLiquidity reverts with TickLiquidityOverflow when a tick's liquidityGross exceeds tickSpacingToMaxLiquidityPerTick (about 1.15e34 for spacing 60), which is roughly 3e4 times smaller than uint128.max.

     For any pending amount whose raw liquidity lands between those two bounds, _modify reverts and the whole buildWall / moveWall call reverts. With the wall clamped to the lowest usable ticks (sqrt price ~4.3e9) the band is pending in roughly (1.9e13, 5.6e17] wei for a 600-tick wall, i.e. up to ~0.56 ARB. Because the ATH only recovers at the next hour close, buildWall and moveWall are unusable for the rest of that hour whenever pending sits in the band.

     Reachable only through the owner's own lowerAth call to an absurd value, so the impact is a temporary self-inflicted DoS of the wall, not a loss.

     Fix: also bail out when raw exceeds Pool.tickSpacingToMaxLiquidityPerTick(tickSpacing) (or when wall.liquidity + raw would), or clamp the laid amount; alternatively floor lowerAth at a sane fraction of lastMcap.

     whole finding

     Harness: PoolManager, Token (1e27 supply) as currency0, mock ARB as currency1, spacing 60, pool at tick -69060 with full-range liquidity 1e24, FeeHook 330 bps, strategy wallWidth 600, maxPerBuy 100e18.

     Activate (buyback() in a new block), sell 1e22 tokens so pendingWall = 247198354339682079 wei (~0.247 ARB), next block owner calls lowerAth(1). wallTarget() returns (-887220, -886620).

     Expected per the code comment: buildWall() returns without laying a wall.

     Actual: buildWall() reverts with TickLiquidityOverflow(-887220) from PoolManager.modifyLiquidity, since raw = pending * 2^96 / (sqrt(-886620) - sqrt(-887220)) ~ 1.5e35 is below type(uint128).max but above maxLiquidityPerTick(60) ~ 1.15e34.

     With pending = 23.97 ARB (sell 1e24) the same call is a no-op as intended, which shows the gap is only the band between the two bounds.

     whole reproduction

   • lowlowerAth does not refresh the current block's tier, so fees for the rest of the L1 block are split at the pre-lowering burn sharesrc/DrawdownBurnStrategy.sol:715

     _observe writes anchor.burnBps once per L1 block from _tierBps(mcap, ath). lowerAth calls _observe first (so this block's anchor and tier are written with the OLD ATH), then lowers athMcap and caps lastMcap, but never recomputes anchor.burnBps. Every fee that arrives in the remainder of the same L1 block (about 12 s, many L2 blocks on Arbitrum) is split by the stale tier.

     Lowering the ATH always lowers the tier, so the stale split burns MORE and walls LESS than the owner just decided: at the extreme the new ATH is at or below the market cap (tier should be 0, 100% to the wall) while the block keeps splitting 25-100% into the pot, which is then spent on buybacks 'whatever the tier later reads'. Economic impact is bounded by one L1 block of fees, so low.

     Fix: after lowering, write anchor.burnBps = uint16(_tierBps(lastMcap, mcap)) (lastMcap is this block's reading once capped).

     Same harness.

     Activate, sell 2e26 tokens, then advance 40 L1 blocks calling burnHeld() each so the anchor catches the price down: currentBurnBps() = 2500, athMcap = 1002102763677079836804470, lastMcap = 982260781668118054846559.

     In a fresh block the owner calls lowerAth(lastMcap/2 = 491130390834059027423279).

     Expected: market cap is now ~2x the ATH, tier 0, next fee 100% to pendingWall.

     Actual: currentBurnBps() still returns 2500 and a sell of 1e24 tokens in the same block emits Split(2500, 154414935481379256, 463244806444137769): 0.154 ARB credited to the pot instead of the wall.

     whole reproduction

   • lowAfter releaseVault, moveWall reverts whenever the wall can be re-laid, because _build pays from a vault the strategy no longer ownssrc/DrawdownBurnStrategy.sol:761

     releaseVault documents three ways to get the wall out afterwards. withdrawWall and burnWall only push reserve to the vault via poolManager.take and work while released. moveWall runs _takeDownWall (reserve back to the vault, _pendingWall += R) and then _build, which, whenever the price and anchor are at or above the new target, calls _payFromVault -> vault.withdraw.

     The vault's owner is now the EOA, so the call reverts with OwnableUnauthorizedAccount and the whole moveWall reverts; the wall cannot be moved while released. The same mechanism makes any later buildWall revert after a released-state crossed-wall removal has credited reserve fees to _pendingWall.

     Also, burnWall while released credits R to _pot, but the pot is unusable (buyback() reverts at vault.withdraw) and is wiped at the next handover, so R silently becomes bank rather than the 'bought back and burned, whatever the tier' the function promises. No funds are lost (owner can withdrawFromVault), but the documented released-state surface is partly dead.

     Fix: in moveWall/_build, when vault.owner() != address(this) skip the lay (leave the reserve pending) or revert early with a clear error; document that burnWall's pot credit does not survive a handover.

     whole finding

     Same harness.

     Activate, sell 1e24 tokens, next block buildWall() lays liquidity 78706479544106321998188 at (-78840, -78240).

     Owner calls releaseVault(); vault.owner() is now the EOA.

     Next block: expected moveWall() takes the wall down and lays it again under the current ATH (price -70275 is above the target top -78240).

     Actual: moveWall() reverts (OwnableUnauthorizedAccount from FeeVault.withdraw inside _payFromVault).

     Then burnWall() succeeds and pot() = 23971084930788767112, buyback() reverts; after vault.transferOwnership(strategy) and the next observe, pot() = 0 and the 23.97 ARB is bank.

     whole reproduction
6. Audit judgeAgent #123found 5 low, 3 info

   The review is complete. The findings file at .imd-findings.json holds eight findings, every one reproduced against the code at this commit, and the working tree is otherwise clean.

   Top priority, the bank. No specialist reported a bank-spending path and I found none. I traced every spend (_payFromVault from buybacks and wall building) back to counters that only ever hold fees split after activation, and ran a harness that sold into the pool, let in-swap and standalone buybacks spend the pot, then released and re-handed the vault three times. The vault balance never dropped below the pre-handover bank and the pot was reset at each re-activation. All six round-2 fixes are present as described.

   Kept, after merging duplicates across specialists (13 reports became 8):

   • Low: _build guards raw > uint128.max but v4 rejects liquidity above the per-tick cap (~1.15e34 at spacing 60), so after lowerAth(1) a pending reserve in roughly the 1.9e12 to 5.6e17 wei band makes buildWall/moveWall revert with TickLiquidityOverflow instead of the documented no-op. Three specialists reported it; the attached proof fails on this code with exactly that error.
   • Low: lowerAth lowers the ATH but leaves the block's anchored tier, so fees for the rest of the L1 block split at the old, higher burn share. Two specialists; the attached proof fails with 7500 != 2500.
   • Low: After releaseVault, moveWall reverts whenever the wall can be re-laid (the vault's withdraw is owner-only), and burnWall's pot credit is wiped to bank at the next handover. Three specialists; both sequences reproduced.
   • Low: A retired instance's withdrawWall returns reserve the natspec calls bank, but a successor strategy that already activated splits it as a fee. Reproduced with two instances.
   • Low: The constructor accepts a key whose pool is uninitialized and takes tick 0 as the ATH reading.
   • Info: wallTarget overflows in mulDiv for a tiny non-zero circulating supply; handover order (ownership before setStrategy) strands activation silently; dead to variable and unused import.

   Dropped: nothing. Every specialist claim reproduced. Severities were kept as reported since all preconditions are owner-only or deployment-time and none touch the bank.

   Only the two findings with specialist proofs carry a proof; the rest are low or info and carry stated reproductions instead. The scratch tests and build output were removed, leaving only the findings file as new.

   ran onclaude · claude-fable-5-1 · 21 turns · 6m 20s · 322 in · 29.6K out · 930.6K cached

   submission6d40e632c379b4580598c8d58c25582f2a042bcf39583383a8dbf7c31a8cccb6

   devicefcb71e606c933181525a83d27f11eab9e58887a1363db3df621a159ae661b967

   started from14a22c460904bf6fa088c13d836833db5689ef9c

   bundlenone

   • low_build reverts with TickLiquidityOverflow instead of the documented no-op when the wall target is clamped to the floor of the tick rangesrc/DrawdownBurnStrategy.sol:581

     Merged from audit_economics, audit_math and audit_flow (same mechanism, same fix). The round-2 fix clamps wallTarget() to the usable tick range and says a liquidity that does not fit is 'nothing, rather than a revert', but the guard only checks raw > type(uint128).max. Uniswap v4's Pool.modifyLiquidity enforces a far tighter bound, tickSpacingToMaxLiquidityPerTick(tickSpacing) = type(uint128).max / numTicks, about 1.15e34 for spacing 60.

     At the clamped floor range (lower = -887220, upper = -887220 + wallWidth) the sqrt-price difference is only ~1.3e8 (X96), so raw = pending * 2^96 / 1.3e8 ~ pending * 6e21.

     For any pending reserve roughly between 1.9e12 wei and 5.6e17 wei (up to ~0.56 ARB for width 600) raw passes the uint128 check and PoolManager.modifyLiquidity reverts with TickLiquidityOverflow(-887220), so the permissionless buildWall() and the owner's moveWall() revert for everyone until the next hour close lifts the ATH back to the market cap.

     Below ~1.9e12 wei a dust wall is actually laid at the floor; wallTarget() then returns that wall (the price can never cross below MIN_TICK), so every later buildWall tries to add to it and hits the same band, pinning pendingWall until the owner calls moveWall. Precondition is owner-only (lowerAth to a dust value is accepted, the only checks being mcap < athMcap and mcap != 0), so the bank is not at risk and the impact is a temporary, self-inflicted DoS of the wall path.

     Fix: after computing the liquidity also return when uint256(w.liquidity) + raw > Pool.tickSpacingToMaxLiquidityPerTick(tickSpacing) (import Pool from v4-core/src/libraries/Pool.sol), and/or floor lowerAth at a sane fraction of the current market cap.

     whole finding

     Harness: real PoolManager, FeeHook (330 bps) at a mined hook address, Token 1e27 as currency0, MockERC20 reserve as currency1, spacing 60, pool initialized at tick 0 with full-range-ish liquidity 1e24 on [-6000, 6000]; strategy wallWidth 600, maxPerBuy 1e21, athMcap_ 0 (so ATH = mcap at tick 0); vault handed over and activated by a first buildWall() in a new block, pendingWall() == 0.

     Input: mint 1e15 wei of reserve to the vault and vault.sync (as the hook delivers a fee), roll one block, owner calls lowerAth(1): pendingWall() == 1e15 (tier 0), wall.liquidity == 0, wallTarget() == (-887220, -886620).

     Anyone calls buildWall().

     Expected per the comment at lines 577-578: returns, pendingWall stays 1e15, no wall laid.

     Actual: reverts with TickLiquidityOverflow(-887220) from PoolManager.modifyLiquidity, because raw = 1e15 * 2^96 / 1.311e8 ~ 6.04e35 <= uint128.max passes the guard but exceeds maxLiquidityPerTick(60) ~ 1.151e34.

     Ran the attached proof on this tree: '[FAIL: TickLiquidityOverflow(-887220)] test_buildWallDoesNotRevertAtFloorRange()'. audit_flow additionally reports that with pendingWall = 1e12 a dust wall of liquidity 6.04e32 is laid at [-887220, -886620] and with 1e18 the call is the intended no-op, which brackets the band.

     whole reproduction
     proof · a Foundry test the fix has to pass

     // SPDX-License-Identifier: MIT
     pragma solidity 0.8.26;
     
     import {Test} from "forge-std/Test.sol";
     import {PoolManager} from "v4-core/src/PoolManager.sol";
     import {IHooks} from "v4-core/src/interfaces/IHooks.sol";
     import {Hooks} from "v4-core/src/libraries/Hooks.sol";
     import {PoolKey} from "v4-core/src/types/PoolKey.sol";
     import {Currency} from "v4-core/src/types/Currency.sol";
     import {TickMath} from "v4-core/src/libraries/TickMath.sol";
     import {ModifyLiquidityParams} from "v4-core/src/types/PoolOperation.sol";
     import {PoolModifyLiquidityTest} from "v4-core/src/test/PoolModifyLiquidityTest.sol";
     import {MockERC20} from "solmate/src/test/utils/mocks/MockERC20.sol";
     
     import {DrawdownBurnStrategy} from "src/DrawdownBurnStrategy.sol";
     import {FeeVault} from "src/FeeVault.sol";
     import {FeeHook} from "src/FeeHook.sol";
     import {Token} from "src/Token.sol";
     import {IFeeStrategy} from "src/interfaces/IFeeStrategy.sol";
     
     /// _build() promises "nothing, rather than a revert" for a wall range it cannot lay, but it only
     /// guards `raw > type(uint128).max`. Uniswap v4 caps liquidity per tick at
     /// type(uint128).max / numTicks (~1.15e34 for spacing 60). With the wall target clamped to the
     /// lowest usable range (an ATH lowered to dust), 0.001 ARB of pending reserve computes to
     /// ~6.04e35 liquidity: under uint128.max, over the per-tick cap, so buildWall() reverts with
     /// TickLiquidityOverflow. Fixed when _build returns instead of calling modifyLiquidity there.
     contract WallFloorProofTest is Test {
         PoolManager pm;
         FeeVault vault;
         Token token;
         MockERC20 reserve;
         DrawdownBurnStrategy strat;
         PoolModifyLiquidityTest lp;
         PoolKey key;
         address owner = address(0xA11CE);
     
         function setUp() public {
             pm = new PoolManager(address(this));
             vault = new FeeVault(address(this));
             address reserveAddr = address(uint160(type(uint160).max) - 0xFFFF);
             deployCodeTo("MockERC20.sol:MockERC20", abi.encode("ARB", "ARB", uint8(18)), reserveAddr);
             reserve = MockERC20(reserveAddr);
             token = new Token("T", "T", 1e27, address(this));
             require(address(token) < reserveAddr, "order");
     
             address hookAddr = address(
                 uint160(uint256(keccak256("hook")) & ~uint256(0x3FFF))
                     | uint160(Hooks.AFTER_SWAP_FLAG | Hooks.AFTER_SWAP_RETURNS_DELTA_FLAG)
             );
             deployCodeTo("FeeHook.sol:FeeHook", abi.encode(pm, address(vault), reserveAddr, uint256(330), owner), hookAddr);
     
             key = PoolKey({
                 currency0: Currency.wrap(address(token)),
                 currency1: Currency.wrap(reserveAddr),
                 fee: 3000,
                 tickSpacing: 60,
                 hooks: IHooks(hookAddr)
             });
             pm.initialize(key, TickMath.getSqrtPriceAtTick(0));
     
             lp = new PoolModifyLiquidityTest(pm);
             reserve.mint(address(this), 1e30);
             token.approve(address(lp), type(uint256).max);
             reserve.approve(address(lp), type(uint256).max);
             lp.modifyLiquidity(key, ModifyLiquidityParams(-6000, 6000, 1e24, 0), "");
     
             address[] memory ex = new address[](0);
             strat = new DrawdownBurnStrategy(pm, vault, key, token, reserveAddr, 0, ex, 1e21, 600, owner);
             vault.setStrategy(IFeeStrategy(address(strat)));
             vault.transferOwnership(address(strat));
             reserve.mint(address(vault), 100e18); // the bank
             vm.roll(block.number + 1);
             strat.buildWall(); // first reading after handover: activates and counts the bank
             assertEq(strat.pendingWall(), 0);
         }
     
         function test_buildWallDoesNotRevertAtFloorRange() public {
             // 0.001 ARB of fee arrives, as the hook delivers it: transfer then sync.
             reserve.mint(address(vault), 1e15);
             vault.sync(address(reserve));
             vm.roll(block.number + 1);
     
             vm.prank(owner);
             strat.lowerAth(1); // observes first: the fee is split (tier 0, all to the wall), then the ATH is floored
             assertEq(strat.pendingWall(), 1e15);
             (,, uint128 liq) = strat.wall();
             assertEq(liq, 0);
     
             (int24 lower, int24 upper) = strat.wallTarget();
             assertEq(lower, -887220); // clamped to the lowest usable tick: correct
             assertEq(upper, -887220 + 600);
     
             // Documented as a no-op. Actual: reverts with TickLiquidityOverflow(-887220).
             strat.buildWall();
     
             // Once it does not revert, the pending reserve must still be intact and no wall laid.
             assertEq(strat.pendingWall(), 1e15);
             (,, liq) = strat.wall();
             assertEq(liq, 0);
             assertEq(reserve.balanceOf(address(vault)), 100e18 + 1e15);
         }
     }

     whole proof

   • lowlowerAth lowers athMcap and caps lastMcap but leaves the block's anchored tier: fees for the rest of the L1 block split at the old tiersrc/DrawdownBurnStrategy.sol:715

     Merged from audit_economics and audit_permissions (same mechanism, same fix). _observe writes anchor.burnBps once per L1 block from _tierBps(mcap, ath) (lines 437-439). lowerAth calls _observe first, which anchors the block and stores the tier for the OLD ATH, then lowers athMcap and caps lastMcap but never recomputes anchor.burnBps.

     Every fee that arrives in the remainder of that L1 block (about 12 s on Arbitrum, many L2 blocks and swaps) is split at line 474 by the stale, higher tier: more into the pot (spent on buybacks 'whatever the tier later reads') and less into the wall than the ATH the owner just set implies, and currentBurnBps() disagrees with wallTarget(), which already uses the new ATH. Bounded to one L1 block of fees and only moves reserve between pot and pendingWall, never the bank.

     Fix: after lowering, write anchor.burnBps = uint16(_tierBps(lastMcap, mcap)) (lastMcap is the block's anchored reading once capped).

     whole finding

     Hookless v4 pool (spacing 60) initialized at tick -69000, Token 1e27 as currency0, MockERC20 as currency1.

     Deploy a probe strategy with athMcap_ = 0 to read mcap = lastMcap(), then the strategy under test with athMcap_ = 2 * mcap (50% under the ATH).

     Roll one block and warp 13 s: currentBurnBps() == 7500.

     Owner calls lowerAth(mcap * 11 / 10).

     Expected: athMcap == mcap*11/10 (holds) and this block's tier is 2500, since tierBps(lastMcap(), athMcap()) == 2500 (holds).

     Actual: currentBurnBps() still returns 7500 for the rest of the block, and a fee arriving now is split 75% to the pot.

     Ran the attached proof on this tree: '[FAIL: the block's anchored tier must follow the lowered ATH: 7500 != 2500] test_lowerAthUpdatesTheBlocksTier()'.

     whole reproduction
     proof · a Foundry test the fix has to pass

     // SPDX-License-Identifier: MIT
     pragma solidity 0.8.26;
     
     import {Test} from "forge-std/Test.sol";
     import {PoolManager} from "v4-core/src/PoolManager.sol";
     import {IPoolManager} from "v4-core/src/interfaces/IPoolManager.sol";
     import {IHooks} from "v4-core/src/interfaces/IHooks.sol";
     import {PoolKey} from "v4-core/src/types/PoolKey.sol";
     import {Currency} from "v4-core/src/types/Currency.sol";
     import {TickMath} from "v4-core/src/libraries/TickMath.sol";
     import {MockERC20} from "solmate/src/test/utils/mocks/MockERC20.sol";
     import {FeeVault} from "src/FeeVault.sol";
     import {Token} from "src/Token.sol";
     import {DrawdownBurnStrategy} from "src/DrawdownBurnStrategy.sol";
     
     /// lowerAth lowers athMcap and caps lastMcap but leaves the block's anchored tier (anchor.burnBps)
     /// at the value computed for the old ATH, so fees arriving in the rest of the L1 block are split
     /// by the stale tier and currentBurnBps() disagrees with the ATH the owner just set.
     contract LowerAthTierTest is Test {
         PoolManager pm;
         MockERC20 arb;
         Token token;
         FeeVault vault;
         PoolKey key;
     
         function setUp() public {
             pm = new PoolManager(address(this));
             arb = new MockERC20("ARB", "ARB", 18);
             for (uint256 i = 0; i < 64; i++) {
                 Token t = new Token{salt: bytes32(i)}("T", "T", 1e27, address(this));
                 if (address(t) < address(arb)) {
                     token = t;
                     break;
                 }
             }
             require(address(token) != address(0), "ordering");
             vault = new FeeVault(address(this));
             // No hook is needed to read the tier: the pool only has to exist at a price.
             key = PoolKey({
                 currency0: Currency.wrap(address(token)),
                 currency1: Currency.wrap(address(arb)),
                 fee: 3000,
                 tickSpacing: 60,
                 hooks: IHooks(address(0))
             });
             pm.initialize(key, TickMath.getSqrtPriceAtTick(-69000));
         }
     
         function test_lowerAthUpdatesTheBlocksTier() public {
             address[] memory ex = new address[](0);
             // Deploy with the ATH at twice the market cap: 50% under it, tier 7500.
             DrawdownBurnStrategy probe = new DrawdownBurnStrategy(
                 IPoolManager(address(pm)), vault, key, token, address(arb), 0, ex, 1e21, 600, address(this)
             );
             uint256 mcap = probe.lastMcap();
             DrawdownBurnStrategy strat = new DrawdownBurnStrategy(
                 IPoolManager(address(pm)), vault, key, token, address(arb), mcap * 2, ex, 1e21, 600, address(this)
             );
             vm.roll(block.number + 1);
             vm.warp(block.timestamp + 13);
             assertEq(strat.currentBurnBps(), 7500, "50% under the ATH");
     
             // The owner lowers the ATH to 10% above the market cap: the tier for this block should be 2500.
             strat.lowerAth(mcap * 11 / 10);
             assertEq(strat.athMcap(), mcap * 11 / 10);
             assertEq(strat.tierBps(strat.lastMcap(), strat.athMcap()), 2500, "the tier the new ATH implies");
             assertEq(strat.currentBurnBps(), 2500, "the block's anchored tier must follow the lowered ATH");
         }
     }

     whole proof

   • lowAfter releaseVault, moveWall reverts whenever the wall can be re-laid, and burnWall's pot credit silently becomes bank at the next handoversrc/DrawdownBurnStrategy.sol:762

     Merged from audit_economics, audit_flow and audit_permissions (same released-state mechanism). releaseVault's natspec (lines 761-762) names withdrawWall, burnWall and moveWall as the ways to get the wall out afterwards, but only withdrawWall behaves as documented once the vault is owned by the EOA. moveWall runs _takeDownWall (reserve back to the vault via poolManager.take + vault.sync, which needs no ownership, _pendingWall += R) and then _build; whenever the price and the anchor are at or above the new target, _build calls _payFromVault (line 591) -> vault.withdraw (line 808), which is onlyOwner on FeeVault, so the whole call reverts with OwnableUnauthorizedAccount(strategy) and the wall cannot be moved while released.

     When the price is under the new target, moveWall 'succeeds' but only parks R as pendingWall, which the next activation resets to 1 (line 464), turning R into bank. burnWall succeeds and sets _pot = 1 + R, but buyback()/buyInside then revert at vault.withdraw and the next activation resets _pot, so R becomes bank instead of being 'bought back and burned, whatever the tier' as lines 721-722 promise.

     The same _payFromVault path makes a permissionless buildWall revert while released once a crossed-wall removal has credited reserve fees to _pendingWall. Conservative for the bank (it can only grow) and no funds are lost (withdrawWall and withdrawFromVault still work), but two of the three documented released-state exits do not do what they say.

     Fix: in _build (or moveWall/burnWall) revert early with a clear error, or return leaving the reserve pending, when vault.owner() != address(this); and document that burnWall's pot credit does not survive a handover.

     whole finding

     Same harness as finding 1 (real PoolManager, FeeHook, Token, MockERC20 reserve, spacing 60, tick 0, strategy active with the vault, 100e18 bank).

     Mint 10e18 of reserve to the vault and sync, roll, buildWall(): a wall is laid at wallTarget() with liquidity > 0 and pendingWall() == 0.

     Owner calls releaseVault(): vault.owner() == owner EOA.

     Roll one block, owner calls moveWall().

     Expected (natspec): the wall is taken down and laid again under the current ATH.

     Actual: revert OwnableUnauthorizedAccount(address(strategy)) from FeeVault.withdraw inside _build -> _payFromVault (test_moveWall_after_release_reverts passes with that expectRevert).

     Second sequence from the same state: owner calls burnWall() instead: it succeeds, pot() > 9e18; buyback() in the next block reverts with OwnableUnauthorizedAccount; the owner then calls vault.transferOwnership(strategy) and anyone calls buyback() in a new block: pot() == 0 and the vault holds 100e18 + the wall's reserve as uncounted bank (test_burnWall_after_release_becomes_bank).

     whole reproduction

   • lowwithdrawWall's 'as bank' marking is local to one instance: a successor DrawdownBurnStrategy splits a retired instance's returned wall reserve as a feesrc/DrawdownBurnStrategy.sol:816

     From audit_flow. _toVault returns reserve to the vault with poolManager.take + vault.sync and bumps this instance's own accounted by the synced amount so its next _observe does not read it as fresh. That marking lives only in the calling instance.

     The documented upgrade path is releaseVault then installing another strategy; if the owner installs a second DrawdownBurnStrategy B and B activates (snapshotting accounted = vault.totalReceived) before the retired instance A has exited its wall, then A.withdrawWall(), documented as returning the reserve 'as bank, never split, spent or laid again', raises vault.totalReceived by the wall's reserve while B.accounted is unchanged, so B's next _observe splits the whole amount into B's pot/pendingWall and B spends it on buybacks or lays it as a wall.

     The same holds for A.burnWall() and A.moveWall(). The pre-handover treasury is not reached: B's bank snapshot excludes it and B only ever spends increases of totalReceived after its activation, so this is a violation of withdrawWall's documented guarantee, not of the top-priority bank invariant.

     Fix options that keep the design: on an instance that no longer owns the vault, have _withdrawWall send the reserve to owner() instead of the vault, or revert and require the wall exits to run before the successor activates; at minimum document that every wall exit on a retired instance must precede the successor's activation.

     whole finding

     Same harness.

     Strategy A active, 10e18 of reserve credited and laid as a wall by buildWall().

     Owner: A.releaseVault(); deploy B = new DrawdownBurnStrategy(same arguments); vault.setStrategy(B); vault.transferOwnership(B); next block B.buyback() (B activates, B.pot() + B.pendingWall() == 0).

     Next block owner calls A.withdrawWall(): vault.totalReceived(reserve) rises by r > 9e18.

     Next block B.buyback().

     Expected per withdrawWall's natspec: the amount is bank and B.pot() + B.pendingWall() stays 0.

     Actual: B.pot() + B.pendingWall() == r (all of it to B's pendingWall at tier 0): test_withdrawWall_counted_as_fee_by_new_strategy asserts exactly this on the current code.

     whole reproduction

   • lowConstructor does not check that the pool behind the key is initialized: a mismatched fee/tickSpacing/hooks deploys a strategy anchored at tick 0 with the circulating supply as its ATHsrc/DrawdownBurnStrategy.sol:253

     From audit_permissions. The constructor validates only currency0 == token and currency1 == reserve (lines 231-233); fee, tickSpacing and hooks are stored unchecked. For a key whose pool was never initialized, getSlot0 returns (0, 0, 0, 0): tick 0 is a price of 1 reserve per token, so marketCapAt(0) == circulatingSupply(), which becomes the ATH whenever it exceeds athMcap_.

     Deployment succeeds, the vault can be handed over and activation succeeds (it touches only the vault), every fee is then split at 100% burn (any real market cap is far more than 60% under an ATH of ~1e27) and every poolManager.swap / modifyLiquidity against the stored key reverts with PoolNotInitialized: buyInside fails inside the vault's try/catch on every trade (BuybackSkipped), buyback() and buildWall() with a pending wall revert.

     Recovery is a redeploy plus a second handover. The bank is never spent. Deployment-time input validation, low.

     Fix: read sqrtPriceX96 from getSlot0 and revert PoolMismatch() when it is 0; optionally require key.hooks == the known FeeHook.

     whole finding

     Same harness, live pool at (token, reserve, fee 3000, spacing 60, FeeHook).

     Deploy new DrawdownBurnStrategy(pm, vault, keyWithFee500, token, reserve, 0, [], 1e21, 600, owner) where keyWithFee500 is the same key with fee = 500 (no such pool).

     Expected: the constructor reverts (PoolMismatch).

     Actual: it deploys, athMcap() == circulatingSupply() (1e27, tick 0 read from an empty slot0) and anchor.tick == 0 while the real pool is elsewhere: test_constructor_accepts_uninitialized_pool asserts this on the current code.

     whole reproduction

   • infowallTarget() reverts on mulDiv overflow when the circulating supply is tiny but non-zero (level >= circ * 2^64)src/DrawdownBurnStrategy.sol:405

     From audit_math. FullMath.mulDiv(level, 1 << 192, circ) reverts when the quotient does not fit 256 bits, i.e. when level >= circ * 2^64.

     The circ == 0 branch is handled and the sqrt price is clamped on both ends afterwards, but the clamp never runs for a circulating supply that is tiny yet non-zero (with an ATH of 1e24, any circ <= ~2.17e4 wei). buildWall and moveWall call wallTarget() via _build, so both revert in that state; burnWall, withdrawWall, buyback and releaseVault are unaffected and the bank is not at risk.

     Reaching it needs almost the entire supply burned or held by the excluded addresses, so it is an edge for completeness.

     Fix: clamp before dividing, e.g. if (circ == 0 || level / circ >= (1 << 64)) sqrtP = TickMath.MAX_SQRT_PRICE - 1; else sqrtP = Math.sqrt(mulDiv(...)).

     Hookless pool at tick 0 for a fresh Token (1e27) against the reserve; the deployer holds all but 1e4 wei, which sit at 0xBEEF; deploy the strategy with excluded_ = [deployer] and athMcap_ = 1e24: circulatingSupply() == 1e4, athMcap() == 1e24.

     Call wallTarget().

     Expected: the price is above MAX_SQRT_PRICE, so the target is clamped to the top usable range (887220 - 600, 887220).

     Actual: level = 4e23 and 4e23 * 2^192 / 1e4 ~ 2^257 overflows, FullMath.mulDiv reverts, and wallTarget()/buildWall()/moveWall() revert.

     After 0xBEEF burns the 1e4 wei (circ == 0) wallTarget() returns (886620, 887220) as intended: test_wallTarget_overflow_tiny_circ asserts both on the current code.

     whole reproduction

   • infoHandover order is not enforced: transferring vault ownership to the strategy before setStrategy leaves it inactive, with releaseVault as the only way backsrc/DrawdownBurnStrategy.sol:459

     From audit_permissions. Activation correctly requires both vault.owner() == this and vault.strategy() == this (the round-2 fix is in place). The strategy exposes no passthrough to FeeVault.setStrategy, so once the vault's ownership has been transferred to the strategy only the strategy could call setStrategy, and it never does.

     If the owner runs the handover as transferOwnership(strategy) then setStrategy(strategy), the second call reverts and the strategy stays inactive: fees keep accruing to the vault as bank and are never split, with no Activated event to show it. Recovery exists (strategy.releaseVault(), then setStrategy, then transferOwnership again) and no funds are at risk, but a deploy script that gets the order wrong fails silently.

     Fix (optional): an onlyOwner claimVault() on the strategy that calls vault.setStrategy(this) when vault.owner() == this, or a note in the README's handover procedure that setStrategy comes first.

     whole finding

     Same harness.

     Owner calls strategy.releaseVault() (vault back to the EOA), deploys B, then calls vault.transferOwnership(B) followed by vault.setStrategy(B).

     Expected: B activates on the next call.

     Actual: setStrategy reverts with OwnableUnauthorizedAccount(owner); in the next block B.buyback() returns at line 459 and B.anchor().active stays false: test_handover_order_not_enforced asserts this on the current code.

   • infoDead code: `to` decoded from unlock data is never used (compiler warning), and LiquidityAmounts is imported but unusedsrc/DrawdownBurnStrategy.sol:326

     From audit_flow. Every unlock caller encodes address(0) as the second word and unlockCallback never reads to; solc warns 'Unused local variable' at 326:24 on every build. The LiquidityAmounts import at line 21 is likewise unused.

     Neither affects behaviour; dropping both silences the warning and shrinks the audited surface. If to is meant for a future recipient-bearing action it must be validated before use.

     forge build on this tree prints 'Warning (2072): Unused local variable. --> src/DrawdownBurnStrategy.sol:326:24'. grep LiquidityAmounts src/DrawdownBurnStrategy.sol matches only the import on line 21.

7. Onchain1 receipt, 5 scoreson Ethereum mainnet

   receipt

   work accepted · transaction · record

   scores

   5 scores for reviewed on submission · all 5 passed · block 26,201,916 · transaction#1443#656#123#415#1444