Unknown hackers have attempted to launch a second 51% attack on Vertcoin (VTC) but ended up paying for the privilege out of their own pockets.

As Vertcoin’s lead maintainer James Lovejoy revealed in a report on the attack on Dec. 2, a malicious entity targeted cryptocurrency exchange Bittrex in order to manipulate the Vertcoin blockchain.

Hackers paid at least $440 to attack VTC

Vertcoin forked off from Bitcoin (BTC) in 2014 and experienced a major attack in December last year, during which hackers stole funds worth $100,000

This time, however, it appears the exploit was much less successful. 

“Based on the market prices during the attack's preparation and the difficulty of the blocks the attacker produced, we estimate the attacker spent between 0.5-1 BTC to perform the attack,” Lovejoy explained. 

As a result, the hackers appear to have come out with a net loss of between 0.06 BTC ($440) and 0.56 BTC ($4,100): 

“The total value of the block rewards the attack received is 13825 VTC (~0.44 BTC). Given the attack was likely not profitable to perform based solely on block rewards, the motivation for the attack is not certain.”

Fighting for scraps

Bittrex is VTC’s main trading venue. After noticing suspicious activity, Lovejoy requested the exchange halt VTC pairs, which appeared to limit the attack’s success. 

“Given the reorg was just deeper than 600 blocks (Bittrex's confirmation requirement for VTC), it is possible that Bittrex was the original target, but the double-spend portion attack was aborted due to Bittrex disabling their wallet before the fork could be released,” he added.

VTC/USD has fallen around 7% to $0.23 in the past 24 hours, but the move is broadly insignificant within the context of 2019 highs of $0.61 seen in June.

As Cointelegraph reported, Bitcoin remains much more immune to 51% attacks thanks to its provably decentralized structure and unrivaled hash rate.

As well-known pundit Andreas Antonopoulos previously noted, with Bitcoin, such an attack would cost around $1 billion for a 10-minute offensive, something which in itself is all but impossible to achieve.