Polymarket Trading Disrupted After Users Report $2.6M in Losses

Polymarket temporarily restricted trading on Thursday after a security incident drained roughly $2.6 million from user accounts, according to user and on-chain reports. The platform put its international exchange into cancel-only mode, letting users remove orders but not submit or execute new trades, and paused Relayer activity while investigating. It said a compromised external provider, not its core infrastructure, caused the breach; Arkham tracked a wallet linked to the attacker holding about $2.65 million in POL after USDC.e-to-POL swaps through Relay, with on-chain investigators citing about $2.7 million. Polymarket said it fixed the vulnerability, referred the matter to law enforcement and pledged to reimburse affected traders, though individual figures such as one trader’s roughly $800,000 claim were not based on the company’s accounting.