Leaderboard
36All-time rank
Balancer V2
Nov 3, 2025
$128M
Lost
$128M
Recovered
$0
Net loss
$128M
Unrecovered0% recovered
On November 3, 2025, Balancer V2's Composable Stable Pools were exploited for $128M via a rounding-down flaw in batchSwap invariant calculation. Minuscule discrepancies in each transaction compounded across rapid successive swaps, gradually deflating pool reserves across chains.
How the exploit worked
View reproducible PoCPrecision Loss.
Lost: 120M USD
Source: DeFiHackLabs (SunWeb3Sec)
- Target
- DeFi
- Classification
- Token & Share Accounting
- Technique
- Rounding Error
- Attribution
- Unknown
- Chains
EthereumArbitrumBasePolygonSonicOptimism
Event timeline
- Nov 3, 2025Exploit executed — $128M drained via rounding error
- Attributed to Unknown
- Recovery status Unrecovered 0%
Data credits
- DefiLlamaIncident record, amounts, chains, recovery data and logo
- DeFiHackLabsExploit analysis and reproducible proof-of-concept (by SunWeb3Sec)