806 hack event(s)
Description of the event: Digital currency exchange Poloniex, which trades bitcoin and other popular digital currencies such as litecoin, namecoin and dogecoin, has lost 12.3% of its total bitcoin supply in an attack. The exchange took to Bitcoin Forum on 4th March to report it had been compromised by a previously unknown vulnerability in its coding.
Amount of loss: 97 BTC Attack method: Unknown
Description of the event: MtGox was hacked. Losses totalled 850,000 BTC, worth $470m at the time.
Amount of loss: 850,000 BTC Attack method: Stolen hot wallet
Description of the event: On June 8, Feathercoin was attacked by 51%. Before the attack, Feathercoin's total computing power was 0.2GH/s, and during the time of the attack, the computing power doubled 7 times to 1.5GH/s. Thirty-one hours later, an investigation revealed that the attacker took away 580,000 Feathercoin through a double-spending attack on the exchange, at a current price of $63,800.
Amount of loss: $ 63,800 Attack method: 51% attack
Description of the event: Bitcoin exchange Bitfloor suspended operations after the theft of $250,000. The founder Roman Shtylman explained in a post on the Bitcoin Forum that an attacker obtained an unencrypted backup of exchange wallet keys and used these keys to transfer "BitFloor on hand" Most of the coins he held," Shtilman later locked this part of the money at around 24,000 BTC.
Amount of loss: 24,000 BTC Attack method: Private key leak
Description of the event: Bitcoinica was hacked twice in 2012. Hackers stole a total of 61,000 BTC, leading to the bankruptcy of Bitcoinica.
Amount of loss: 61,000 BTC Attack method: Stolen hot wallet
Description of the event: The attacker has a lot of computing power to launch a 51% attack. The interesting thing about the Coiledcoin attack is that it is not economically driven, but purely political. Although this move has caused some protests in the community, it shows how vulnerable the SHA-256 cryptocurrency with low hashing power is to attack.
Amount of loss: - Attack method: 51% attack