BlockFi Hack

TOTAL LOST $1.0B
Critical #14 All-Time Other

Summarize with AI

ChatGPT Perplexity Claude Grok
Affected Chain 2022 Incident surface
Recovered - No recovery reported
All-Time Rank #14 By amount stolen
Protocol Type Exit Scam/Other Target category

Incident Overview

Quick Summary

BlockFi filed for bankruptcy as FTX collapse grips crypto markets. The company filed a lawsuit against Emergent Fidelity Technologies which Sam Bankman Fried owns. The lending platform has 1,000,000,000 $USD in liabilities as a minimum.

Details of the Exploit

BlockFi is a crypto lending platform, that provides lending opportunities using crypto assets as collateral. The platform halted withdrawals on November 11, the day when FTX filed for bankruptcy, citing "significant exposure" to the FTX exchange and Alameda Research hedge fund as well. The company filed for Chapter 11 and a lawsuit against Bankman Fried's Emergent Fidelity Technologies, demanding they turn over collateral that BlockFi claims is owed.

BlockFi estimates it has between 1,000,000,000 $USD and 10,000,000,000 $USD in liabilities, according to the filing. The company owed money to more than 100,000 creditors, and the largest one is Ankura Trust which is owed roughly 729,000,000 $USD.

Incident Report

Protocol / Project BlockFi
Date of Incident
Attack Technique Other
Classification CeFi
Primary Source View Post-Mortem #1 View Post-Mortem #2

Protocol Information

Protocol Type Exit Scam/Other
Official Website blockfi.com/
Protocol Twitter/X @BlockFi
Team Public / Doxxed
Source Code Unverified

Market Context at Time of Hack

Token Categories
BNB Chain Ecosystem
Protocol Links

What the Attacker Needed to Succeed

Understanding the prerequisites for this type of attack helps auditors identify protocols that are most at risk and helps developers build better defenses.

Technical Knowledge Deep understanding of other and Solidity and EVM internals
Capital Required Seed capital to cover gas and initial position setup
On-Chain Access Ability to interact with smart contracts and deploy a custom exploit contract
Protocol Analysis Identification of the exploitable vulnerability in BlockFi's contract logic - root cause: cefi
Execution Speed Precise transaction ordering and timing to exploit the vulnerability within a single atomic block
Obfuscation Plan A strategy to launder and move stolen funds - typically through mixers, cross-chain bridges, or decentralized DEX swaps to resist tracing

What Auditors Should Check

Could this have been caught in audit? Likely — with a thorough Other audit checklist and test coverage

If you're auditing a protocol with similar architecture to BlockFi, these are the critical security checks that could have prevented this incident (November 2022).

  • Verify all logic paths related to Other are guarded by proper access controls and input validation
  • Review privileged functions (owner, admin, governance) for potential abuse vectors - centralization risks should be documented and bounded with timelocks or multi-sigs

Master these auditing techniques with hands-on labs and real exploit scenarios in the Smart Contract Hacking course.

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