Piriform released a new version of the company's popular Windows cleaning software CCleaner to the public yesterday.

The new version ships with two major changes, namely a new Emergency Updater feature, and new default cleaning rules for some programs.

CCleaner 5.36 is available for download from the official company website, and also available as an in-program update for CCleaner Professional customers.

Free users can download the portable version from the builds page which comes without adware.

CCleaner 5.36: Emergency Updater

CCleaner 5.36 Emergency Updater

by Martin Brinkmann on October 25, 2017 in Software - Last Update:October 25, 2017 37
Piriform released a new version of the company's popular Windows cleaning software CCleaner to the public yesterday.

The new version ships with two major changes, namely a new Emergency Updater feature, and new default cleaning rules for some programs.

CCleaner 5.36 is available for download from the official company website, and also available as an in-program update for CCleaner Professional customers.

Free users can download the portable version from the builds page which comes without adware.

Emergency Updater is a new feature of CCleaner that comes with its own executable file -- CCUpdate.exe -- and a new scheduled task called CCleaner Updater.

The integration of the Emergency Updater component in CCleaner is likely a response to the recent hack of the company's infrastructure. Attackers managed to plant malicious code in CCleaner which was distributed for about a month from the official company website.

Piriform released a new version of the program with a new digital signature, but could not distribute it to free users due to a lack of automatic update functionality.

Piriform, which was acquired by Avast in 2017, probably used Avast's Emergency Updater as a blueprint for CCleaner's Emergency Updater functionality.

Avast released the feature back then as an alternative method to update the company's security programs if the default update function failed to do so.

The scheduled task is only added to the Windows machine if you install CCleaner. It is added for users of the free version as well however.

This means that Piriform may push out updates to the program to user machines even if only the free version of CCleaner is installed on these machines.

The task is set to run on system start, and once a day as well.

CCleaner default cleaning rules changes

The second major change of CCleaner 5.36 changes some of the program's default cleaning rules. Default rules are those that are set when you run the program for the first time.

Probably the biggest change in this regard is that CCleaner won't delete browsing session data anymore by default. Users of the program who did not pay attention to the cleaning rules have had their browsing session deleted when they ran CCleaner.

The change affects Firefox, Chrome, Edge, Opera, Safari and Thunderbird.

CCleaner 5.36 does not clean Windows Defender's scan history, the MRUs of Microsoft Office, and most recently used documents and other MRU files of Windows Explorer anymore.

Closing Words

Emergency Updater is a useful feature, provided that attackers won't exploit it successfully to push malicious code to user systems. CCleaner users who install the program on their Windows PCs may want to disable the task to avoid this from happening.