Submitted by Bauchibred
Take a look at the OPFaultVerifier implementation:
https://github.com/code-423n4/2024-12-unruggable/blob/8c8cdc170741d4c93287302acd8bca8ff3d625a2/contracts/op/OPFaultVerifier.sol#L67-L91
From the documentation, the Optimism Fault proof verifier assumes that blacklisted games only matters for withdrawals, where as this is one of the reason why the blacklisted logic is implemented (i.e., blockage of withdrawals), this is not the only reason.
To put this in retrospect, The optimism portal allows the GUARDIAN to permanently blacklist a game, when the game resolves incorrectly, thats to show this is no case to be trusted to be used in our verification logic.
This can be seen from the Optimism Portal itself.
See the implementation of the portal from the previous code4rena audit:
First, the blacklist is implemented as a simple mapping in the OptimismPortal2 contract:
OptimismPortal2.sol#L127-L130
Only the guardian can blacklist dispute games and this is done only in the case where the game is resolving incorrectly:
OptimismPortal2.sol#L439-L445
Which then brings us to the fact that if a game is blacklisted, then it is a wrong premise to be used for verification and we should check for this in the Verifier.
High. While the primary and most visible impact of blacklisting a game is blocking withdrawals, the blacklisting mechanism actually invalidates a dispute game entirely since they are resolving incorrectly which then means we shouldnt use this in our OP Verifiers, otherwise we would be accepting an incorrectly resolving game.
Ensure the game being verified is not blacklisted.
thomasclowes (Unruggable) acknowledged and commented:
Picodes (judge) commented:
Bauchibred (warden) commented:
Picodes (judge) commented:
thomasclowes (Unruggable) commented:
Picodes (judge) commented:
thomasclowes (Unruggable) commented:
Picodes (judge) commented:
thomasclowes (Unruggable) commented:
Unruggable mitigated:
Status: Mitigation confirmed. Resolved by adding finalized mode validation to check that the selected game is finalized.
For this audit, 4 reports were submitted by wardens detailing low risk and non-critical issues. The report highlighted below by oakcobalt received the top score from the judge.
The following wardens also submitted reports: Bauchibred, rbserver, and ZanyBonzy.
