If you don't know the current situation in
@code4rena, here is the brief:
Code4rena hosted K2 competition, which was the last one before announcing a winding down.
After distributing rewards to participants and sending judging fees, two SRs,
@MaxZuvex and
@0xArav, found what appears to be a Sybil attack.
They found that two wardens created their accounts days before the competition ended and submitted findings clearly copied from other wardens' work.
One submission belonged to a less-duplicated issue group, which increases their profit, and the other one was a QA report that resembles another warden's QA report and got 1st place.
Code4rena Team believes that the Judger is the one responsible for this, as he was one of the few people who had access to the submission before closing.
Code4rena was able to recover funds from these 2 newly created accounts (propabbly as KYC process and newly created account payout delays).
Code4rena asked the Judger to return the funds, but he has not responded to date.
C4 head judge will review the issues, remove duplicate sybil issues, review QA reports, and post the final result, and wardens will receive the amount deducted from their reward.