Polymarket is set to refund users after a security exploit, stemming from a compromised third-party vendor, resulted in the theft of approximately $2.94 million. The attack allowed hackers to inject malicious code into the prediction market's front-end, impacting at least 11 user accounts. Polymarket has stated that the frontend issue has been resolved and all affected customers will be fully reimbursed. This incident follows a previous hack last month where a company wallet was compromised, leading to a loss of roughly $600,000.