CCleaner v5.33.6162 Compromised with Back Door: Uninstall or Update Immediately

The Piriform program CCleaner is an admin’s best friend. It helps you reclaim some storage on your laptops or workstations and can help you clean up any registry quirks. However, if you’ve got CCleaner v5.33.6162 running or CCleaner Cloud 1.07.3191, it has a very serious security flaw and requires immediate updating.

Avast, owners of CCleaner, announced, “We found that the 5.33.6162 version of CCleaner and the 1.07.3191 version of CCleaner Cloud was illegally modified before it was released to the public.” There is a back door in it that could allow a bad actor unfettered access to your machine.

Users of CCleaner Cloud version 1.07.3191 should have received an automatic update. Users of CCleaner 5.33.6162, however, will likely need to manually update the application.

Know your EULAs, Don’t Use CCleaner Free Version in Corporate Environments

If you are using CCleaner Free at work, you are in direct violation of the software’s terms of use and could be subject to fines. So, on top of being at risk for hacking, you could get audited and cause your organization to be fined, which definitely won’t go over well with your boss. CCleaner has licenses for corporate environments and they’re reasonably priced, so we recommend you invest in them rather than risk fines and/or legal fees.

How Do I Find Out Which Version of CCleaner I’m Running?

First off, you can easily check your version type in the application on the top left, like so:

If you are not sure where it may be deployed within your network, there are also a variety of scans you can perform that will turn up what’s running on workstations.

If you have any questions about CCleaner, your overall network security, or how to run a network scan, email us or give us a call at 502-240-0404!