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Reproduced Exploit

Notional — malicious treasury manager can burn treasury tokens via makerFee

1. Treasury manager signs 0x orders to sell harvested COMP for WETH. 2. _validateOrder never requires makerFee == 0 and takerFee == 0. 3. Malicious manager sets makerFee = full WETH proceeds to itself. 4. Treasury COMP leaves; manager keeps COMP + WETH; treasury nets 0.

Jan 2022•Other•untagged•2 min read

Chain

Other

Category

untagged

Date

Jan 2022

Source

AuditVault

PoC & write-upPoC for your local evm-hack-analyzerAuditVault PoCs

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Source & credit. Reproduction of a public audit finding curated by AuditVault — the original finding: 24657-h-03-a-malicious-treasury-manager-can-burn-treasury-tokens-b. Standalone Foundry PoC and full write-up: 24657-h-03-a-malicious-treasury-manager-can-burn-treasury-tokens-b_exp in the evm-hack-registry mirror.

Vulnerability classes: fee-calculation · direct-drain · fot-slippage · treasury-multisig

Reproduction: a self-contained Foundry PoC that compiles & runs in an isolated project with only forge-std — no fork, no RPC, no anvil_state. Full trace: output.txt. PoC: test/24657-h-03-a-malicious-treasury-manager-can-burn-treasury-tokens-b_exp.sol.

Key info#

ImpactHIGH — manager signs 0x order with makerFee = proceeds; treasury loses assets for free
ProtocolNotional
Vulnerable codeEIP1271Wallet
Bug classfee-calculation
FindingCode4rena — Notional, 2022-01 · #24657 · reporter leastwood / shw
Reportcode4rena.com/reports/2022-01-notional
SourceAuditVault
StatusAudit finding — caught in review, not exploited on-chain. Reproduced as a standalone local PoC.
Compiler^0.8.24 (PoC)

This is an audit finding, not a historical on-chain incident. The PoC keeps the vulnerable logic verbatim (marked @> VULN) and reduces dependencies to the minimum needed to show the claimed harm.

TL;DR#

  1. Treasury manager signs 0x orders to sell harvested COMP for WETH.
  2. _validateOrder never requires makerFee == 0 and takerFee == 0.
  3. Malicious manager sets makerFee = full WETH proceeds to itself.
  4. Treasury COMP leaves; manager keeps COMP + WETH; treasury nets 0.

The vulnerable code#

See test/24657-h-03-a-malicious-treasury-manager-can-burn-treasury-tokens-b.sol — the @> VULN marker is on the blamed line (line 155 in the synthetic).

Root cause#

Missing zero-fee checks in EIP1271Wallet._validateOrder.

Preconditions#

Protocol operating conditions that make the path reachable (see finding report). No exotic privileges beyond those the real call path requires.

Attack walkthrough#

From output.txt: the Exploit.run() path executes the attack end-to-end and requires the harm.

Diagrams#

flowchart TD A[Setup reduced protocol state] --> B[Trigger vulnerable path] B --> C[VULN line executes] C --> D[Harm asserted]

Impact#

Treasury assets burned/donated to the manager at no cost to the taker path.

Sources#

Sources & further analysis#

Reproductions & code

Alerts & third-party analyses

  • Web3Sec X hacked database: search.
  • Rekt leaderboard: search.
  • Solodit incident search: search.

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