A successful ransomware attack on a single company has spread to at least 200 organizations, according to cybersecurity firm Huntress Labs, making it one of the largest criminal ransomware attacks in history.
The attack, which first became known on Friday afternoon, is believed to be linked to the prolific ransomware gang REvil and immortalized by Kaseya, an international company that remotely controls programs for businesses that manage Internet services for businesses.
Kaseya announced Friday afternoon that it had been attacked by hackers and warned all of its customers to stop using its service immediately.
At least four of Kaseya’s immediate customers were hacked, said John Hammond, a senior security researcher at Huntress who is helping with Kaseya’s response.
With these Kaseya customers running an untold number of businesses, it’s unclear how many will fall victim to ransomware over the weekend, but Huntress’s number is already around 200, Hammond said.