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Submission Details
Severity: low
Invalid

`transferFrom` Return Value Is Ignored in `createGameWithToken()` and `joinGameWithToken()`

0xshield

Description:

In createGameWithToken() and joinGameWithToken(), the return value of the transferFrom() function is ignored. Although most ERC-20 tokens revert on failure, ignoring the returned bool may cause the function to proceed even if the token transfer fails silently (in the case of non-standard ERC-20 implementations).
This breaks the checks-effects-interactions pattern and may leave the contract in an inconsistent state or open to user error.

Recommended Mitigation:

Always check the return value of transferFrom():

- winningToken.transferFrom(msg.sender, address(this), 1);
+ require(winningToken.transferFrom(msg.sender, address(this), 1), "Token transfer failed");
- winningToken.transferFrom(msg.sender, address(this), 1);
+ require(winningToken.transferFrom(msg.sender, address(this), 1), "Token transfer failed");
Updates

Appeal created

m3dython Lead Judge 7 months ago
Submission Judgement Published
Invalidated
Reason: Non-acceptable severity
Assigned finding tags:

Broken Token Game Creation

createGameWithToken and joinGameWithToken functions will revert because they attempt transferFrom without requiring the user to first approve

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