An admin wallet for layer-2 blockchain ZKsync was compromised on Tuesday with the hacker taking off with $5 million worth of ZK tokens. The stolen funds were the "remaining unclaimed tokens from the ZKsync airdrop," ZKsync wrote on Twitter , before saying that "necessary security measures are being taken." The protocol's ZK token has dropped almost 14% over the past 24 hours. Volume has increased by 96% to $71 million in the same period. ZKsync said the attack was an isolated incident and that it is confined to the token airdrop contract.