IQ AI — Adversary can win proposals with voting power as low as 4%

Source & credit. Reproduction of a public audit finding curated by AuditVault — the original finding: 50064-h-01-adversary-can-win-proposals-with-voting-power-as-low-as. Standalone Foundry PoC and full write-up: 50064-h-01-adversary-can-win-proposals-with-voting-power-as-low-as_exp in the evm-hack-registry mirror.

Vulnerability classes: quorum-supply-drift · governance-voting-power-snapshot · governance/proposal-manipulation

Reproduction: self-contained Foundry PoC with only forge-std — no fork. Full trace: output.txt. PoC: test/50064-h-01-adversary-can-win-proposals-with-voting-power-as-low-as_exp.sol.

Key info#


Impact	HIGH — malicious proposal executes with only 4% of supply (comment claimed 25%)
Protocol	IQ AI — `TokenGovernor`
Vulnerable code	`GovernorVotesQuorumFraction(4)` with OZ denominator 100 → 4% quorum
Bug class	Quorum misconfiguration / comment-vs-code (treated as 4% effective quorum)
Finding	Code4rena 2025-01-iq-ai · #50064 · H-01 · reporter DoD4uFN
Report	code4rena.com/reports/2025-01-iq-ai
Source	AuditVault
Status	Judge maintained High (Agent ownership / LP risk on low-cap agent tokens).
Compiler	`^0.8.24` (PoC)

TL;DR#

Constructor sets GovernorVotesQuorumFraction(4) with comment "quorum is 25% (1/4th)".
OZ quorumDenominator() defaults to 100, so quorum = supply * 4 / 100 = 4%.
Attacker with 4% of votes meets quorum alone and can execute proposals (e.g. Agent takeover).
Fix: GovernorVotesQuorumFraction(25).

The vulnerable code#

SOLIDITY

// constructor:
quorumNumeratorValue = 4; // claimed 25% (1/4th) — wrong for denominator 100

function quorum(uint256) public view returns (uint256) {
    // @> VULN: numerator 4 / denominator 100 ⇒ 4% (intended 25%)
    return (token().getPastTotalSupply(t) * quorumNumerator(t)) / quorumDenominator();
}

Root cause#

Misread of OZ quorum fraction API: 4 means 4%, not "1/4". Comment documents the intended 25% but code ships 4%.

Preconditions#

Attacker holds ≥ 4% of voting power (delegated).
Other holders do not vote against (or lack voting power at snapshot).

Attack walkthrough#

Whale holds 100M supply; attacker gets 4M (4%) and self-delegates.
governor.quorum() == 4M.
Attacker proposes Agent takeover, votes For, executes — succeeds.
With true 25% quorum (25M), the same 4% vote would fail.

Diagrams#

flowchart TD A["GovernorVotesQuorumFraction 4"] --> B["denominator = 100"] B --> C["quorum = 4% of supply"] C --> D["Attacker holds 4%"] D --> E["propose + vote + execute"] E --> F["Agent takeover succeeds"] G["Intended 25%"] -.->|would block| E

Impact#

Low-cap agent tokens can have multiple 4% holders; governance of Agent (holding LP) is capturable far below the documented 25% threshold.

Taxonomy#

genome: quorum-supply-drift, governance-voting-power-snapshot, governance/proposal-manipulation
severity/high · sector/governance · platform/code4rena

Sources#

AuditVault finding #50064
Code4rena report 2025-01-iq-ai
Repo: code-423n4/2025-01-iq-ai · src/TokenGovernor.sol L55
OZ: GovernorVotesQuorumFraction v5.2.0 L62–L74

Sources & further analysis#

Reproductions & code

Standalone PoC + full trace: 50064-h-01-adversary-can-win-proposals-with-voting-power-as-low-as_exp (evm-hack-registry mirror).
AuditVault finding: 50064-h-01-adversary-can-win-proposals-with-voting-power-as-low-as.

Alerts & third-party analyses

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

These dashboards index community alerts tweets, post-mortems, and independent write-ups. Reach them through the protocol name above to cross-check this reproduction against other analyses.

Source-level debugger — step opcodes and Solidity in sync