Polymarket halts trading after $2.65 million breach

Polymarket suspended trading on 29 October after a third-party breach exposed users to unauthorised withdrawals, with estimated losses reaching $2.65 million.

The prediction market restricted its exchange to cancel-only mode, blocking new orders while allowing users to cancel existing positions.

“One of our third party providers was compromised, and we have referred this to relevant law enforcement,” said Polymarket in its official status update.

Blockchain analytics linked a suspected attacker’s wallet to approximately $2.65 million in stolen assets following transactions involving POL tokens and Relay.

“Anyone who has been impacted will be made whole,” Polymarket said.

Polymarket’s reliance on external service providers highlights how vulnerabilities beyond a platform’s core systems can expose users to security risks.

The incident puts user protection and reimbursement commitments at the centre of Polymarket’s response as it works to maintain confidence in its prediction markets.

Following the update, Polymarket resumed international trading after fixing the issue, while work continued on addressing the incident and reimbursing affected users.