Hacker exploits Polymarket UMA adapter, steals over $520K, POL drops 1%

Polymarket UMA CTF Adapter exploited on Polygon; losses exceed $520k, POL slips

• On-chain analyst ZachXBT reported an exploit of Polymarket’s UMA CTF Adapter on Polygon on May 22.
• Attack rate was about 5,000 POL every 30 seconds, with confirmed losses above $520,000 and reports reaching roughly $660,000.
• Attacker address 0x8F98075db5d6C620e8D420A8c516E2F2059d9B91 dispersed funds across 15 wallets.
• Polymarket stated the target was the UMA CTF Adapter, not its core contracts on Polygon.
• POL fell about 1% in the past hour, trading near $0.091 at the time of reporting.
• UMA moved from $0.477 to $0.462 during the incident, a drop of about 3.3%.
• Polymarket also confirmed account breaches tied to a third‑party authentication provider, with some USDC wallets drained to minimal balances.
• May recorded 19 DeFi hacks with total losses around $38.2 million, according to DeFiLlama.

Implications and watchpoints

• Short‑term sell pressure for POL is typical after high‑profile exploits.
• Recovery depends on how quickly the flaw is identified, patched, and user losses addressed.
• Polygon’s recent Giugliano hard fork aimed at faster finality, which supports settlement reliability.
• Key factors to monitor include the final loss tally, any extension of impact to other contracts, and reimbursement commitments.