Polymarket has suspended trading after a third-party provider compromise led to unauthorized withdrawals from user accounts. The prediction market platform said Thursday it had identified and fixed the issue, referred the matter to law enforcement, and promised that affected users will be made whole.
Polymarket (Credits: CoinDesk)
Polymarket Trading Suspended: What Happened
Users on the platform’s international venue began reporting Thursday that their assets were withdrawn without approval, per CoinDesk. Polymarket’s status page confirmed the incident: “One of our third party providers was compromised,” the statement said, adding that trading was halted while the team works to bring the platform back online.
The exchange was placed in cancel-only mode — traders can cancel outstanding orders but cannot place new ones — and relayer actions were paused while the incident is investigated.
Polymarket Breach Losses and Investigation
Arkham data cited by The Block shows a suspected attacker wallet holding about $2.65 million in POL after multiple USDC.e-to-POL swaps through Relay, with funds then moved to different addresses. The Wall Street Journal reports the money was transferred in more than 900 transactions. One trader told reporters he personally lost about $800,000, warning others to lock down their accounts.
The WSJ reports, citing a person familiar with the matter, that the source of the issue was a security flaw in DebugBear, a performance-monitoring vendor used on Polymarket’s website. DebugBear posted on X that it had been impacted by an ongoing security incident and advised customers to remove its embed code from their websites.
Notably, this is the second such incident in recent months. In June, Polymarket reported that another third-party vendor had been breached, with malicious JavaScript injected into the platform’s front-end — an attack that saw roughly $3 million taken from users.
Also Read: Polymarket Brings Ultra-Short Five-Minute Crypto Prediction Markets to U.S. Platform | Stanley Druckenmiller’s First X Post Backs Hyperliquid Venture
Source: CoinDesk — read the full story there.
