Arcadia Finance hacker used reentrancy exploit, team demands return of funds By Cointelegraph

The Arcadia Finance attacker used a reentrancy exploit to drain $455,000 from the decentralized finance (DeFi) protocol, according to a July 10 post-mortem report issued by the app’s development team. A “reentrancy exploit” is a bug that allows an attacker to “reenter” a contract or interrupt it during a multi-step process, preventing the process from being completed correctly.

The team has sent a message to the attacker demanding the return of funds within 24 hours and threatening police action if the hacker fails to comply.