Attacker Drains $234,000 From Balancer V1 Using Precision Flaw
Balancer V1, launched in 2020, is an automated market maker that issues Balancer Pool Tokens, or BPT, to liquidity providers. The exploit underscores the residual risk in legacy decentralized-finance contracts: V1 pools are immutable and no longer actively maintained, while flaws in fixed-point arithmetic can become economically significant when reserves are pushed to extreme levels. The newer Balancer V2 system was not identified as the affected product.
Blockchain security firm SlowMist disclosed on Aug. 31, 2026 that the attacker used nested flash loans from Spark, Aave, Morpho and Uniswap V3 to drive the pool’s WBTC reserve close to zero. A rounding-down error then allowed about 4,408.8 BPT to be minted with one satoshi of WBTC. The tokens were redeemed for DPI, USDC, WETH and WBTC, causing an estimated $234,000 loss.
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The history behind this eventBalance Coin Plunges 99% After $915,000 Oracle Exploit
Balance Coin, or BLC, is an algorithmic stablecoin issued by Balance Protocol on BNB Chain and overseen by governance organization 42DAO. The token was designed to track the U.S. dollar through collateralized vaults backed largely by BTCB. The incident underscores a longstanding risk in decentralized finance: weak safeguards around price oracles and liquidation systems can rapidly undermine collateral, liquidity and confidence in a stablecoin’s peg.
On July 22, blockchain security firm PeckShield estimated that the exploit cost 42DAO about $915,000, while SlowMist attributed the attack to manipulation of a BTCB price oracle that triggered improper vault liquidations. The attacker minted about 4.5 million BLC and routed the tokens through PancakeSwap V2 for USDT and BTCB. BLC collapsed from roughly $0.9954 to about $0.0014, a decline of more than 99%, wiping out nearly all of its nominal market value.
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