On March 22, Offchain Labs disclosed two serious vulnerabilities in the Optimism OP Stack fraud proofs, which were identified during a testnet review. The vulnerabilities were communicated privately to the OP Labs team, fostering a collaborative effort to enhance security across the Ethereum network. This proactive approach allowed for a coordinated response, ensuring that the issues could be addressed before being exploited in production environments. The discovery was part of a broader initiative to secure the OP Stack system, which is crucial given its widespread use across various Layer 2 blockchains. A subsequent audit contest by Sherlock DeFi, starting March 27, has pushed these OP Stack fault proofs closer to deployment on the OP Mainnet. Additionally, Stage 1 of the fault proofs is set to launch this summer.