$BTC Here are some well-known hacking attacks related to Bitcoin and cryptocurrency in general:

⸻

1. Mt. Gox (2014)

• Lost: ~850,000 BTC (at the time over $450 million, now — billions).

• What happened: A Japanese exchange that processed ~70% of global BTC transactions at the time suffered a years-long theft due to vulnerabilities in the system.

⸻

2. Bitfinex (2016)

• Lost: ~120,000 BTC (over $70 million at the time, now — over $7 billion).

• What happened: Hackers exploited a bug in the multi-signature system from a third-party provider. Some of the Bitcoins were laundered for years until the FBI arrested the suspects in 2022.

⸻

3. Ronin Network (Axie Infinity) — 2022

• Lost: ~$625 million (not only BTC, but also ETH/USDC).

• What happened: The North Korean-controlled Lazarus group hacked the private keys of validators.

⸻

4. NiceHash (2017)

• Lost: 4,700 BTC ($64 million at the time).

• What happened: A breach of the password management system — hackers accessed the service's wallet.

⸻

5. Poly Network (2021)

• Lost: ~$611 million (ETH, BSC, USDT, etc.).

• What happened: Exploitation of vulnerabilities in smart contracts. Interestingly, the hacker (or “white hat”) returned the funds.