VERDICT —OUT OF SCOPE
Root cause is private-key / signer compromise — the on-chain contract behaved exactly as written. No pre-deployment source audit or bytecode review reaches the key-custody perimeter; this is operational-security territory (HSM/MPC hygiene, key rotation, hot-wallet isolation). Bytecode would show nothing wrong.
▰ METHOD
PRIVATE KEY
PRIVATE-KEY
Root cause
Root-cause analysis not yet published. The incident description below contains all currently available signal — review the attack transaction directly for definitive forensics.
Forensic narrative
The margin trading lending platform bZx tweeted that the private keys controlling Polygon and Binance Smart Chain (BSC) deployment appeared to have been leaked, resulting in a loss of funds. The bZx smart contract itself was not compromised, and the deployment, governance and DAO vault of Ethereum were not affected by this incident. Attack method (per SlowMist): Private Key Leakage. Reported loss: $ 55,040,167.
Primary source
https://bzx.network/blog/prelminary-post-mortem ↗Sourced from
slowmist
Technical record
- chain
- ethereum
- protocol
- bZx
- bug_class
- private-key
- date_occurred
- 2021-11-05
- loss_usd
- $55,040,167
- source_id
- sm:bzx::2021-11-05
Related — same bug class· private-key