Popular utility tool CCleaner (short for ‘Crap Cleaner’), which promises to clean up your system for enhanced performance, was hacked to distribute malware directly to its users.

The malware was also programmed to collect a bunch of user data, including:

  • Name of the computer
  • List of installed software, including Windows updates
  • List of running processes
  • MAC addresses of first three network adapters
  • Additional information whether the process is running with administrator privileges, whether it is a 64-bit system, etc.

The malware was found in CCleaner version 5.33, which was actively distributed between August 15 and September 12. What is particularly jarring is that it appears the infected app was signed with a valid certificate Symantec issued to Piriform (recently acquired by Avast).

“To the best of our knowledge, the second-stage payload never activated… It was prep for something bigger, but it was stopped before the attacker got the chance.”

If you have the infected version 5.33, please download and install the latest version here or contact me to update and review your computer.