Polymarket Sets $3.9M Refund Plan After Third-Party Script Compromise

TL;DR: Polymarket says its October 29 incident involved a compromised monitoring script. Its October 30 update put total refunds at $3.9 million, including losses linked to the trading pause. Polymarket has published a more detailed account of the third-party compromise that disrupted its international platform on October 29. The update shifts the focus from whether trading had reopened to how the attack worked and how customers would be compensated. The company’s explanation is also a reminder that an onchain application can depend on offchain website components with access to active user sessions.