Polymarket users lose $2.71M after DebugBear script is compromised

ChainCatcher report: Security firm GoPlus released a vulnerability analysis on social media stating that user assets were stolen from Polymarket’s international site. The RUM script from DebugBear, a third-party performance monitoring service, was compromised via supply chain contamination, resulting in malicious code being delivered to users’ pages and exploited to abuse their trading and signing permissions. On-chain analysis shows the main attack path involved 710 DepositWallets and 731 addresses, with losses totaling approximately $2.71 million; the number of addresses does not represent the number of actual users. Polymarket subsequently confirmed that the issue has been resolved and services have been restored, and pledged full compensation to affected traders, with the actual compensation progress subject to official future announcements.