Ethereum Layer 2 scaling solution Optimism was exploited by a hacker and 20 million tokens were lost. The cyberattack occurred when cryptocurrency market maker Wintermute accidentally added liquidity to the platform and provided a multi-signature address to facilitate transactions. The hacker took advantage of it before the dev team was able to get around this issue.
Wintermue Engaged with Optimism Foundation
Wintermute received a 20 million OP loan from the Optimism Foundation to provide OP token liquidity. The cyber attacker exploited a serious mistake and sent 20 million OP tokens from Layer 1 to Layer 2. The hacker sent 1 million OP tokens to Vitalik Buterin's address.