POLYMARKET HIT BY $3M SUPPLY-CHAIN ATTACK

AI DESK■ 1 MIN READ

FRI, JUN 26, 2026

■ AI-SUMMARIZED FROM 1 SOURCE ▸ TIMELINE

Polymarket customers lost an estimated $3 million after hackers injected malicious code into the platform's frontend through a compromised third-party vendor. The company plans to fully reimburse affected users.

The attack exploited a breach at a third-party vendor integrated with Polymarket's infrastructure, allowing attackers to inject malicious scripts directly into the platform's user interface. Customers unknowingly executed the code while accessing Polymarket, resulting in unauthorized fund transfers. Polymarket disclosed the incident and committed to covering the full $3 million loss for impacted users. The platform has since patched the vulnerability and is conducting a security review of its vendor dependencies. Supply-chain attacks represent a growing threat to crypto platforms and financial services. By targeting trusted third parties rather than companies directly, attackers can bypass security measures and gain access to large user bases. This incident underscores the risks of integrating external code and services without rigorous security vetting.

■ SOURCES

► Bleeping Computer

■ SUMMARY WRITTEN BY AI FROM THE LINKS ABOVE

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POLYMARKET HIT BY $3M SUPPLY-CHAIN ATTACK

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