OFFCHAIN LABS FINDS TWO VULNERABILITIES IN OPTIMISM FRAUD PROOF SYSTEM

Summary from the TLDR Crypto newsletter

Offchain Labs, the company behind the Arbitrum L2, found two severe vulnerabilities in Optimism's fraud-proof system. The exploits, which have now been patched, allowed for fraudulent chain history to be accepted. Fortunately, the vulnerabilities were only on testnet and funds were never at risk.