With this recent malware infection being spread to millions of users, it’s another sign that it’s good to ditch CCleaner. In addition, Lunarsoft has reported in the past about why CCleaner’s usage on Windows has become obsolete in this day and age. Malwarebytes blocks the IP and domains related to this malware. The latest version is available for download here.Īffected versions: CCleaner version and CCleaner Cloud version If you suspect you may have downloaded CCleaner version or CCleaner Cloud version, scan your system for malware.ĬCleaner users that are running older versions or that do not trust the one they are using now are encouraged to update their CCleaner software to version 5.34 or higher. What to do if you think you are affected?įirst of all, check the version of CCleaner on your system. The malware uses a hardcoded C2 server and a domain generating algorithm (DGA) as a backup, to send information about the affected system and fetch the final payload. Other system information that is relevant for the malware like admin privileges, whether it is a 64-bit system, etc.The MAC addresses of the first three network adapters.A list of the currently running processes.A list of installed software, including Windows updates.The malware collects the following information about the infected system: In a press statement the company estimates that 2.27 million people used the affected software. The modified version, 5.33, is made available from August 15 until September 12 when version 5.34 was released. From the statistics brought out by Piriform, CCleaner has been downloaded 2 billion times in total, 5 million times every week. It is difficult to say at this moment how many users might have been affected, but the numbers could be huge. They are also investigating how the files coming from their servers were modified before being released to the public. Piriform is aware of the situation and is acting to prevent further damage. The incident was discovered and reported by Talos. In case you are wondering why they were on those servers, Avast acquired Piriform, the original publishers of CCleaner, a few months ago.

Threat actors have managed to change the files that were being delivered by Avast servers hosting CCleaner updates. In a supply chain attack that may be unprecedented in the number of downloads, servers hosting CCleaner, a popular tool for cleaning up the PC, has been delivering a version of the said software with malware.

Ccleaner piriform 5.33