(KRON/CNN) — Hackers have now targeted a type of personal computer cleaning software.

Security researchers say hackers compromised CCleaner. They say it is a sophisticated attack that affected more than 2 million computers.

CCleaner deletes unneeded files and web browser caches to keep windows computers free of junk.

Hackers were able to place malware into a new version released in August.

Researchers advise windows users to check if they are running compromised versions.

If so, delete the app and install the new safe version.WHAT OTHERS ARE CLICKING ON:

>> MORE TOP STORIES