Major Cryptocurrency Thefts

Learn from real-world examples of major cryptocurrency thefts and hacks. Understanding these incidents helps prevent future attacks and improves security awareness.

Real incidents that resulted in significant financial losses

Study them to understand common vulnerabilities and improve your security practices.

Mt. Gox Hack (2014)

February 2014
$460 million
Ongoing legal proceedings

One of the most infamous cryptocurrency exchange hacks in history, where approximately 850,000 BTC were stolen.

What Happened

  • 850,000 BTC stolen from the exchange
  • Affected over 24,000 users worldwide
  • Exchange filed for bankruptcy protection
  • Led to increased security measures in the industry

Key Lessons

  • Never store large amounts on exchanges
  • Use hardware wallets for significant holdings
  • Regular security audits are essential
  • Transparency in operations is crucial

Coincheck Hack (2018)

January 2018
$534 million
Exchange compensated users, improved security

The Japanese exchange stored a large balance of NEM (XEM) in a “hot” wallet connected to the internet. Hackers exploited weak security protocols, drained the wallet, and transferred hundreds of millions in tokens to various addresses. At the time it was the largest crypto exchange hack ever. It exposed how even major platforms can neglect basic wallet security (e.g., keeping large reserves online).

What Happened

  • 523 million NEM tokens stolen
  • Hackers gained access to hot wallet
  • Exchange had weak security measures
  • No multi-signature protection implemented

Key Lessons

  • Hot wallets are vulnerable to attacks
  • Multi-signature wallets provide better security
  • Regular security assessments are necessary
  • Insurance coverage is important for exchanges

Poly Network Attack (2021)

August 2021
$611 million
Most funds recovered, security improved

A sophisticated attack on the Poly Network, cross-chain protocol, resulted in one of the largest DeFi hacks ever. Hackers tricked the system into releasing assets without legitimate cross-chain permission. It underscored the extreme risk in cross-chain bridges and led to one of the rare cases where the attacker later returned a large portion of the funds (claiming “white-hat” intent).

What Happened

  • Hacker exploited smart contract vulnerability
  • Affected multiple blockchains (Ethereum, BSC, Polygon)
  • Attacker eventually returned most funds
  • Highlighted DeFi security risks

Key Lessons

  • Smart contract audits are critical
  • DeFi protocols need extensive testing
  • Cross-chain bridges are high-risk targets
  • Bug bounty programs can help identify vulnerabilities

Ronin Network Bridge Hack (2022)

March 2022
$615 million
Ongoing investigation, security enhanced

The Ronin sidechain for the Axie Infinity game had its validator set compromised. With control over key nodes, hackers withdrew funds from the bridge contract to their own addresses. A high-profile gaming ecosystem was hit, showing that even applications with large user bases and brand recognition are vulnerable. It exposed how validator-centric architectures can collapse.

What Happened

  • Hackers took control of the five validator nodes
  • Social engineering attack on team members
  • Affected the popular Axie Infinity game
  • The breach remained undetected for five days

Key Lessons

  • Social engineering is a major threat
  • Decentralisation limits matter
  • Multi-signature wallets prevent single points of failure
  • Regular key rotation is essential
  • Gaming platforms are attractive targets

Wormhole Bridge Exploit (2022)

February 2022
$326 million
Losses covered by Jump Crypto

A critical vulnerability in the Wormhole bridge allowed attackers to mint 120,000 wrapped ETH without collateral.

What Happened

  • Smart contract vulnerability exploited
  • Attacker minted fake wrapped ETH
  • Affected Solana and Ethereum bridges
  • Jump Crypto covered the losses

Key Lessons

  • Bridge security is paramount for DeFi
  • Code audits must be thorough
  • Insurance and backup funds are necessary
  • Cross-chain protocols need extra scrutiny

FTX Collapse

November 2022
$400 million
Bankruptcy proceedings continue; partial asset recovery ongoing through U.S. courts.

Once one of the largest crypto exchanges, FTX collapsed in November 2022 amid massive liquidity issues and alleged internal fund misuse, followed by a mysterious $400 million hack hours after bankruptcy filing.

What Happened

  • Alameda Research and FTX misused customer deposits
  • Users were unable to withdraw funds as panic spread
  • Post-bankruptcy, unauthorized transfers drained remaining wallets
  • Sam Bankman-Fried was later arrested and convicted

Key Lessons

  • Centralized custodians require independent auditing
  • Transparency and segregation of funds are non-negotiable
  • Legal frameworks still lag behind crypto innovation

WazirX Hack

July 2024
$234 million
Funds lost

Attackers exploited a multisig wallet setup of the Indian exchange (with 5 issuer signatories + 1 custodian). They created a malicious contract upgrade, bypassed controls, and drained funds — reportedly linked to the state-sponsored Lazarus Group. This hack demonstrated that even “well-structured” custody setups can be compromised by contract logic attacks.

What Happened

  • Smart contract vulnerability exploited
  • Exchange’s multisignature wallet was compromised
  • The stolen funds were quickly funneled through mixers and cross-chain bridges
  • Investigators linked the attack to the Lazarus Group

Key Lessons

  • Proof-of-reserves claims may be misleading
  • Upgrades of contract logic must be rigorous controlled
  • Insurance and backup funds are necessary

Private Loss

November 2024
$3 million
Funds lost

Address posoing was applied. A scammer generated an address with the same first four characters as the victim’s real deposit address and sent a tiny amount of 0.000001 SOL to it, making the fake address appear in the victim’s transaction history. As a result, victim transferred 7M $PYTH ($3.08M) to scammer.

What Happened

  • Scammer generated a look-alike address with the same prefix as the real one
  • Sent a dust transaction to the victim’s wallet
  • The fake address appeared in the victim’s transaction history
  • Victim copied it without verification and transferred 7M PYTH (~$3.08M)

Key Lessons

  • Never copy wallet addresses from transaction history
  • Always double-check the full address, not just the first or last few characters.
  • Use trusted address books or saved verified contacts in your wallet
  • Confirm high-value transfers with a test transaction first
  • Even small dust transactions can be part of an advanced scam

Private Loss

November 2024
$0 (129) million
Funds returned

A careless investor nearly lost $129 million in USDT tokens after copying a spoofed deposit address from their transaction history. The scammer had previously created an address that mimicked the victim’s legitimate deposit address (same last six characters) and sent a tiny 1.01 USDT transaction, causing the fake address to appear in the wallet’s history. When the victim later copied the “familiar” address for a large transfer, the funds went directly to the scammer. Fortunately, the scammer returned the everything within an hour!

What Happened

  • The attacker crafted an address closely resembling the victim’s deposit wallet.
  • They sent a tiny dust transfer so the fake address would show up in the victim’s transaction list.
  • The victim later reused that address for a large transfer, unknowingly sending 129M USDT to the scammer.

Key Lessons

  • Never reuse addresses from your wallet history — always verify manually
  • Check every character of an address before confirming a transaction
  • Small test transfers can save you from multi-million-dollar mistakes

Bybit Exchange Hack

February 2025
$1.5+ billion
Ongoing threat, international response

Allegedly tied to the state-sponsored Lazarus Group, attackers exploited a cold-wallet transfer mechanism. A routine Ethereum move was manipulated, giving thieves access to large sums from Bybit’s offline storage.

What Happened

  • The cryptocurrency exchange Bybit was hacked in what became the biggest crypto exchange theft
  • Used sophisticated social engineering
  • Attackers gained access to cold wallet system by exploiting a vulnerability in a third-party wallet tool
  • North Korean high-skilled hacking group has been systematically targeting cryptocurrency platforms and users worldwide.

Key Lessons

  • Geopolitical threats affect crypto security
  • Advanced persistent threats require robust defenses
  • International cooperation is necessary

Learning from History

These incidents have shaped the cryptocurrency industry and led to improved security practices

Security Evolution

Each major incident has led to improved security standards, better practices, and enhanced protection measures.

Community Awareness

These events have educated the crypto community about risks and the importance of security best practices.

Regulatory Response

Major incidents have prompted regulatory frameworks and compliance requirements to protect users.

What's Next?

You’ve seen how devastating crypto thefts can be — even major platforms and experienced users can fall victim to theft and deception in the crypto world. Now it’s time to learn real defense skills.