Ethereum Classic Hack

TOTAL LOST $1.7M
Medium Forged Proof ethereum classic
Affected Chain ethereum classic Incident surface
Recovered - No recovery reported
All-Time Rank #837 By amount stolen
Year 2020 Incident year

Incident Report

Protocol / Project Ethereum Classic
Date of Incident
Affected Chain(s) ethereum classic
Attack Technique Forged Proof
Classification Bridge & Cross-Chain

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 forged proof and Solidity and EVM internals
Capital Required Seed capital to cover gas and initial position setup
On-Chain Access Ability to interact with ethereum classic smart contracts and deploy a custom exploit contract
Protocol Analysis Identification of the exploitable vulnerability in Ethereum Classic's contract logic - root cause: bridge & cross-chain
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 Forged Proof audit checklist and test coverage

If you're auditing a protocol with similar architecture to Ethereum Classic, these are the critical security checks that could have prevented this incident (August 2020).

  • Verify all logic paths related to Forged Proof 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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