Polymarket's rewards wallet was drained of roughly $700K through a six-year-old compromised private key. User funds were not affected by the breach.

Onchain sleuth ZachXBT flagged a potential exploit of Polymarket's UMA CTF Adapter on Polygon, with $520K reportedly drained so far.

ZachXBT said that Polymarket’s UMA smart contract has been exploited for at least $520,000, pointing to an attacker address receiving hundreds of small transactions.