Bitcoin owners are being warned after cybercriminals launched a large-scale campaign to steal truckloads of the cryptocurrency.
Security experts uncovered the threat after discovering malicious code which was loaded up on hundreds of thousands of websites.
The cybercriminals spread their Bitcoin stealing malware by breaching StatCounter, according to a post by ZDNet.
And there are over 688,000 websites that allegedly load this script.
However, this malicious code is intended to have one major target – cryptocurrency exchange Gate.io.
ESET malware researcher Matthieu Faou discovered the Bitcoin security threat.
He said the malicious code hijacks any Bitcoin transactions made through the web interface of Gate.io.
Faou said the code, which was first added on November 3, secretly replaces any Bitcoin address the user enters with one controlled by the attacker.
Speaking to ZDNet, he said: “A different Bitcoin address is used for each victim.
“We were not able to find the attackers’ main Bitcoin address. Thus, we were not able to pivot on the blockchain transactions and find related attacks”.
ZDNet contacted Gate.io but did not receive a response at the time of writing.
However, the tech site said Gate.io admins have removed the StatCounter script from their site.
And Faou said: “Gate.io doesn’t use StatCounter anymore.
“Thus, Gate.io customers should be safe now.”
The ESET security expert also said it was impossible to estimate how much hackers had stolen via this malware campaign.
In other Bitcoin news, analysts have predicted that the price of the cryptocurrency could be on the verge of a year-end rally.
Mati Greenspan, senior market analyst at eToro, expects Bitcoin to experience a Christmas boom as its price goes on the rise.
He said: “In traditional markets, it’s very common to see a stock rally leading up to the end of the year due to the increased activity in the private sector during the holidays.
“It may be too early to say this, after all we’ve only seen very moderate crypto gains this week, but it is very possible that we might see a Santa Claus rally in the crypto markets.”
He added: “The gains are being led by Bitcoin Cash ahead of the hard fork next week. It’s kind of funny to see that after all this sideways movement, a possible break out could come from a disagreement in the BCH community of all places.
“In any case, the fire doesn’t usually care where the spark came from. Upward momentum has a way of snowballing in financial markets no matter what the drivers of that momentum may have originally been.”