ZKsync: The recovered ETH will gradually be exchanged for ZK tokens, and the return plan is subject to voting ZKsync has released a security incident investigation report that previously involved $5 million in ZK tokens. On April 13th, attackers used stolen administrator keys to mint 11.18 million unclaimed ZK tokens from three airdrop distribution contracts, and exchanged approximately 6.71 million of them for 1116 ETH in the following two days. The development team Matter Labs immediately froze the relevant accounts after discovering the anomaly on April 15th. After the ZKsync Security Committee issued a 72 hour "safe harbor" ultimatum, the attacker returned 90% of the funds and received a 10% bounty on April 23. The remaining funds are currently held by the Security Committee, and the subsequent disposal will be decided by the community governance. After investigation, it was found that the incident was caused by the use of an unsafe 1/1 multi signature management mode in the airdrop contract, while retaining the token casting function that should have been removed. ZKsync stated that the incident only affected three specific airdrop distribution contracts, and the mainnet protocol and governance system were not compromised. To prevent similar incidents, the project party will implement improvement measures such as regular rotation of multiple signatures and upgrading of monitoring systems. The recovered ETH will gradually be exchanged for ZK tokens, and the final return plan needs to be approved by the token council through voting. The investigation shows that the key may have been leaked by a former employee's account, and no evidence of malicious intent was found from the former employee.