Entertainmint — a creator retargets raise currency after minting

Source & credit. Reproduction of a public audit finding curated by AuditVault — the original finding: 48439-stealing-tokens-from-protocol-ottersec-none-entertainmint-pd. Standalone Foundry PoC and full write-up: 48439-stealing-tokens-from-protocol-ottersec-none-entertainmint-pd_exp in the evm-hack-registry mirror.

Vulnerability classes: vuln/logic/incorrect-state-transition · vuln/logic/missing-check

Key info#

TL;DR#

A creator can edit raise currency while the raise is Scheduled. Scheduled is true before presale and again between presale end and public-sale start. Presale minting has already happened by the second window, and the update does not care.

This run starts in that gap: the goal of 10 units of a worthless 18-decimal token is already minted, and raise.balance is 10 ether units. Another project has 10 WETH in the same contract. updateCurrency points the raise at WETH. withdraw pays raise.balance of the current currency, so 10 WETH moves to the creator. The other project is still owed 10 WETH and the contract's WETH balance is 0.

The fix requires block.timestamp < presaleStart. That check returns false here, so the currency stays the worthless token and no WETH moves.

The vulnerable code#

function updateCurrency(address next) external {
    require(msg.sender == attackerRaise.owner, "owner");
    require(scheduled(), "scheduled");
    // @> VULN: currency changes after presale tokens were already minted.
    attackerRaise.currency = next;
}

function updateCurrencyFixed(address next) external returns (bool) {
    if (block.timestamp >= attackerRaise.presaleStart) return false;
    attackerRaise.currency = next;
    return true;
}

Root cause#

Currency and the numeric balance are independent fields. Withdraw pays the balance in whatever currency is set at the end. The scheduled-gap update runs after minted is already the goal, so a filled presale in a cheap token becomes a claim on a valuable token.

Preconditions#

The caller is a registered creator and the owner of this raise, not the protocol admin. Presale has filled 10 units. Another raise's 10 WETH sits in the contract. The timestamp is inside the gap after presale and before the public sale. One block, no warp: presale bounds are already in the past relative to the replay timestamp.

Attack walkthrough#

1. The raise is scheduled. minted is 10 ether. Currency is the worthless token.
2. The contract holds 10 WETH credited to the other project.
3. updateCurrency sets WETH. updateCurrencyFixed returns false.
4. Close the raise. The goal is already met.
5. Withdraw transfers 10 WETH to the creator.
6. Contract WETH is 0. otherWeth is still 10 ether.

Diagrams#

Impact#

The creator receives 10 WETH. Those tokens were another project's deposit. The fixed updater does not change currency, and the WETH withdrawal is 0.

Remediation#

Reject raise and tier edits once block.timestamp reaches presaleStart, including the scheduled gap after presale.

How to reproduce#

cd 48439-stealing-tokens-from-protocol-ottersec-none-entertainmint-pd_exp
forge test -vv

Sources#

• AuditVault finding: https://github.com/Auditware/AuditVault/blob/main/findings/48439-stealing-tokens-from-protocol-ottersec-none-entertainmint-pd.md
• Protocol: https://www.entertainmint.com/

Sources & further analysis#

Reproductions & code

• Standalone PoC + full trace: 48439-stealing-tokens-from-protocol-ottersec-none-entertainmint-pd_exp (evm-hack-registry mirror).
• AuditVault finding: 48439-stealing-tokens-from-protocol-ottersec-none-entertainmint-pd.

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.