Anti-virus company, Avast, has found that a server distributing a version of PC utility CCleaner infected with malware may have been compromised in early July.

Two versions of the commonly used Windows maintenance tool were altered to distribute information-stealing malware, with over 2 million users said to be impacted. Those modified versions include 32-bit CCleaner v5.33.6162 and CCleaner Cloud v1.07.3191. The infection binary was released on August 15 and went undetected for over four weeks.

CCleaner was created by Piriform, but they were acquired by Avast in July 2017. After news broke about the infection, Avast came forward to clarify that the compromise likely occurred before the July acquisition.

“Before we completed the acquisition, the bad actors were likely already in the process of hacking into the Piriform systems. The compromise may have started on July 3rd. The server was provisioned earlier in 2017 and the SSL certificate for the respective https communication had a timestamp of July 3, 2017,” Avast claimed in a blog post.

Avast also claims that no harm was done to the impacted computers, despite the fact that over 2 million people downloaded the infected application release, as the final payload in this attack never activated.

CCleaner v5.34 and CCleaner Cloud v1.07.3214 have been released without the malicious code. Avast claims that only 730,000 users are still running the affected version 5.33.6162 on their systems. The free CCleaner variant doesn’t include automatic updates, meaning that users need to manually download and install the clean version.

NNT advises all impacted users to update to the latest version of CCleaner and to remove all malicious code from your computers.



Read this article on InfoSecurity Magazine





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