An unidentified hacker has mounted several "double spend" attacks on the infrastructure of the Bitcoin Gold cryptocurrency and has managed to amass over $18 million worth of BTG (Bitcoin Gold) coins in the process.
According to a post on the Bitcoin Gold forums, the attacks have started taking place since last Friday, May 18.
The attacker has been deploying a large number of servers to take control of more than half of the Bitcoin Gold's network hashrate in what's known as a "51% attack."
This grants the attacker the ability to modify details of blockchain transactions, an ability he's been using in the last few days to perform a second attack called "double spend," which as the name implies, allows him to spend the same amount of coins twice.
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