Balancer V2 Vulnerability Leads to Significant Financial Losses

According to Foresight News, the SlowMist security team has released an analysis report on a major vulnerability in Balancer V2. This flaw has affected multiple projects and their forked versions across various blockchains, resulting in an estimated total loss of $120 million. SlowMist identified the root cause as a precision loss issue in the integer fixed-point operations used to calculate scaling factors within the composable stable pools of Balancer V2, which are based on Curve's StableSwap stable mathematics. This issue led to small but cumulative price discrepancies during token exchanges. Attackers exploited this vulnerability by executing a series of small exchanges under low liquidity conditions, amplifying the cumulative deviation into substantial profits. SlowMist emphasized that project teams and auditors should enhance their testing coverage for extreme scenarios and boundary conditions, particularly focusing on precise handling strategies under low liquidity conditions.