blockchains-security-toolkit/exploit_analysis/binance_bridge.md
2022-10-07 14:18:34 -07:00

1.3 KiB

🍳 binance bridge


tl;dr

  • an attacker stole 2 million BNB (~$566M USD) from the Binance Bridge
  • the attacker exploited the BNB bridge into minting 2 batches of 1M BNB each, via falsified proofs of deposit on the legacy binance beacon chain
  • the bridge uses vulnerable IAVL verification which the attacker was able to forge, specifically for block 110217401
  • to not draw attention, funds were deposited as collateral on the lending platfor, venus protocol - making it look like it was simply a gigawhale
  • users begain to notice high-slippage swaps and tether blackisting funds
  • the attacker supplied 900k bnb to venus, borrowing a total of $147M in stablecoins, before bridiging to ethereum and l2s, fantom, avalance, polygon
  • bnb paused for 8h, with 26 validators the chain is not really decentralized

Screen Shot 2022-10-07 at 2 15 35 PM

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