CCleaner Cyberattack Leaves Millions of Devices Vulnerable

If you were not aware CCleaner, Avast's free and highly popular maintenance application, was compromised after a cyberattack placed a backdoor into the application itself. While Avast is in the process of tracking down the culprit of the attack, it is essential that IT Admins take steps to secure any potentially affected devices and remove compromised versions of CCleaner when possible.

On September 13, Cisco Talos found that the official download of the free versions of CCleaner 5.33 and CCleaner Cloud 1.07.3191 also contained “a malicious payload that featured a Domain Generation Algorithm as well as hardcoded Command and Control functionality.” What that means is that a hacker infiltrated Avast Piriform’s official build somewhere in the development process build to plant malware designed to steal users’ data.

Avast’s investigation and hunt for the perpetrators continues. In the meantime they advise users who downloaded the affected version to upgrade to the latest version of CCleaner and perform a scan of their computer with a good security software, to ensure no other threats are lurking on their PC.