The DeFi insurance protocol Cozy Finance suffered a security breach on the Optimism network, resulting in the loss of approximately $170,000. Security firm Blockaid identified the exploit early Monday, noting that the attacker moved funds through a bridge within 13 minutes of the initial transaction.
Data from the OP Mainnet explorer indicates the attacker transferred 163,326 USDC.e and burned 1.6 million Cozy PToken. The malicious contract was deployed on September 2, five days before the incident. The exploited token contract, Cozy Set, currently holds a remaining balance of about $4,168 in USDC.e.
This incident marks the second time the protocol has been targeted on Optimism. In August 2025, an attacker stole $427,000 due to a vulnerability in the withdrawal code. Following the latest attack, the protocol appears to have lost nearly its entire deployment on the Optimism network, which was valued at approximately $172,000.
Cozy Finance currently holds the fifth position among insurance protocols on DefiLlama with a total value of about $1.3 million. The security firm Blockaid continues to track the stolen funds and investigate the details of the breach.
