Mt. Gox Hack

TOTAL LOST $473M
Critical #26 All-Time Other

Summarize with AI

ChatGPT Perplexity Claude Grok
Affected Chain 2014 Incident surface
Recovered - No recovery reported
All-Time Rank #26 By amount stolen
Protocol Type Exploit/Other Target category

Incident Overview

Quick Summary

One of the world's largest exchanges, Mt. Gox, declared bankruptcy in 2014 after being hacked, while losing most of its assets. At the time of bankruptcy, the exchange held 200k $BTC.

Details of the Exploit

Mt. Gox was a bitcoin exchange based in Shibuya, Tokyo, Japan. Launched in 2010, it processed more than 70% of all Bitcoin (BTC) transactions worldwide by the beginning of 2014.

At the beginning of 2014, Mt Gox, a bitcoin exchange based in Japan, was the largest bitcoin exchange in the world, handling over 70% of all bitcoin transactions worldwide. By the end of February of that year, it was bankrupt.

Anyone who was using Mt. Gox lost access to their assets, and it has been a cautionary tale for crypto investors. While the assets weren’t all lost, anything that was left has been frozen for years.

The victim of a massive hack, Mt. Gox lost about 740,000 bitcoins (6% of all bitcoin in existence at the time), valued at the equivalent of €473 million at the time and over $3 billion at October 2017 prices. An additional $27 million was missing from the company’s bank accounts.

Block Data Reference

Attacker address:

https://www.blockchain.com/btc/address/1FeexV6bAHb8ybZjqQMjJrcCrHGW9sb6uF

Incident Report

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

Protocol Information

Protocol Type Exploit/Other
Official Website www.mtgox.com/
Team Anonymous
Source Code Unverified

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 Mt. Gox'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 Mt. Gox, these are the critical security checks that could have prevented this incident (February 2014).

  • 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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