@austingriffith
⚖️ Balancer Hack TL;DR:
🧮 Most tokens on Ethereum use 18 decimals, but some don’t.
✖️ Balancer upscales token amounts (to 18-dec) and downscales them back.
🔧 Upscaling always rounded DOWN, but downscaling could round UP or DOWN.
😬 The more scaling steps involved, the greater the chance tiny amounts are lost in edge cases.
🎛️ An attacker tuned swaps to hit those rounding edges.
♾ Each hit gave a tiny profit, so he repeated it hundreds of times in a loop.
https://x.com/BlockSecTeam/status/1986057732810518640
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