If even a small fraction of those systems were compromised an attacker could use them for any number of malicious purposes." "CCleaner claims to have over 2 billion downloads worldwide as of November 2016 and is reportedly adding new users at a rate of 5 million a week. "The impact of this attack could be severe given the extremely high number of systems possibly affected," explained Talos. In other words, to the best of our knowledge, we were able to disarm the threat before it was able to do any harm." "Users of CCleaner Cloud version have received an automatic update. "Before delving into the technical details, let me say that the threat has now been resolved in the sense that the rogue server is down, other potential servers are out of the control of the attacker, and we’re moving all existing CCleaner v users to the latest version," VP of Products Paul Yung wrote in a company release.
Piriform, perhaps unsurprisingly, says everything is taken care of and you can just update and chill. How scared you should be about this malware all depends on who you ask. And then, of course, double check to make sure that your CCleaner is up to date. That's right: you need to restore your computer to a point over a month ago. "Users should also update to the latest available version of CCleaner to avoid infection." "Affected systems need to be restored to a state before Augor reinstalled," the company explains in a blog post.
However, if you want to be extra sure the malware isn't hiding out on your computer, Cisco Talos suggests taking things a step further.