Is CCleaner safe?
Safe to use with care: the official CCleaner is genuine software, but get it only from ccleaner.com, decline extra offers when installing, and know Windows can free space itself.
CCleaner is a real, long-running PC clean-up tool, and its cleaning work happens on your computer rather than being sent to the company. The free version does send usage and device data, and on Android it shows third-party ads.
Its record has two notable marks: in 2017 attackers slipped malicious code into one official release, and in 2020 Microsoft Defender flagged free installers for bundling other software. Cracked “Pro” copies are a real malware risk.
CCleaner was made by Piriform and is now part of Gen. Its licence names Gen Digital Inc. in Arizona as provider for the Americas and Avast Software in Prague for much of Europe; Piriform Software Ltd in London controls user data.[1][2][3]
The real risks
What CCleaner itself says it collects, what regulators and courts have found, its security record and the scams that borrow its name. Each line links to the page it comes from.
What it collects
From CCleaner’s own privacy policy:
- Cleaning runs on your device: browser cookies, saved form data, download history, files and registry entries are processed locally and not sent to the company.[4]
- Your IP address, kept up to 24 months to spot fraud; at activation it is replaced with a city or country code.[4]
- Product usage: events, number of launches, settings, version, install date and licence key.[4]
- Device data: device IDs, Windows version, hardware model, language, approximate location, installed apps and drivers.[4]
- Which security or antivirus apps are on your PC, used to promote products it thinks are relevant to you.[4]
- Analytics through Google Analytics and Logentries on Windows; third-party ad partners such as Google AdMob in the free Android app.[4][2]
App store label. Google Play’s data safety section for CCleaner for Android (developer Piriform) says it shares app activity, installed apps, crash logs, precise location and device IDs with third parties for analytics and advertising. Data is encrypted in transit, and you can ask for deletion.[5]
Regulators and courts
Fines, orders, investigations and lawsuits, newest first. A lawsuit is what the side bringing it alleges until a court decides.
| When | What happened |
|---|---|
| Parent group record, not CCleaner: the FTC proposed an order against Avast, named by CCleaner as its parent in 2017, alleging it sold browsing data through Jumpshot from 2014 to 2020. Avast was to pay US$16.5 million.[6][7] |
Breaches and security flaws
- : CCleaner said Avast had found the attack was very sophisticated and aimed at a select number of large technology and telecoms companies, which Avast contacted directly. CCleaner rebuilt the app on new infrastructure.[10]
- : CCleaner said the 32-bit CCleaner 5.33.6162 and CCleaner Cloud 1.07.3191 shipped with malicious code, used by about 2.27 million people. It sent computer name, IP address and software lists to an outside server, shut down 15 September.[7]
Changes that matter
- : Microsoft Defender began flagging free CCleaner, Recuva, Speccy and Defraggler installers as potentially unwanted for bundling Chrome, Google Toolbar, Avast and AVG. CCleaner disputed parts of Microsoft’s description and changed the builds.[8][9]
Scams that use CCleaner
- Cracked “CCleaner Pro” downloads
- Free “Pro” copies on torrent and warez sites are illegal versions that CCleaner warns can carry keyloggers and steal browsing history and other data. The real Pro version has a free 14-day trial on ccleaner.com.[11]
What to do
In order, with the place to find each one in CCleaner.
- Download it only from ccleaner.com.Get CCleaner from ccleaner.com or your phone’s official app store, never from torrent or “crack” sites.[11]
- Decline extra software when installing.Read each installer screen and choose Decline on offers for other programs such as browsers or antivirus. Microsoft flagged earlier free installers for bundling these.[9][8]
- Keep CCleaner updated.Install the latest version from ccleaner.com. After the 2017 attack, CCleaner told users to update and released a rebuilt version with a new digital signature.[7][10]
- Try Windows’ own Storage Sense first.Start → Settings → System → Storage, then turn Storage Sense on. It clears temporary files and old Recycle Bin items on the main drive without extra software.[12]
When not to use it
- If you only need more disk space on Windows, Storage Sense is built in and free, so you may not need CCleaner at all.[12]
- Never install a cracked or “pre-activated” CCleaner Pro; use the free version or the official trial instead.[11]
What HARD couldn’t verify
Claims you may see elsewhere that HARD couldn’t confirm from a primary source on 7 Nov 2026, so they aren’t in the record above.
- Microsoft’s long-standing support note warning against registry cleaners would not load from Microsoft’s site for HARD to check today.
- The FTC’s final order against Avast, reported as approved in mid-2024, could not be loaded; HARD confirmed only the February 2024 proposed order.
- Claims that CCleaner itself is a virus are not supported: Microsoft classed bundled installers as potentially unwanted, and said the bundled apps were not malware.
Questions
Is CCleaner safe to use?
Yes, with care, when downloaded from ccleaner.com and kept updated. Decline extra offers during install. One official release was hijacked by attackers in 2017, and the company fixed and rebuilt it.
Is CCleaner a virus?
No. In 2020 Microsoft Defender flagged some free installers as potentially unwanted because they bundled other programs, not because CCleaner was malware. Cracked copies from unofficial sites are a different story and can carry malware.
Was CCleaner hacked?
Yes, in 2017. Attackers added code to the 32-bit CCleaner 5.33.6162 and CCleaner Cloud 1.07.3191, used by about 2.27 million people. The company says the outside server was shut down and users were updated.
Does CCleaner collect my data?
Cleaning happens on your PC, but the app sends usage, device and settings data, your IP address and a list of installed apps. The free Android app shows third-party ads and shares some data with ad partners.
Do I need CCleaner on Windows 11?
Often not. Windows’ built-in Storage Sense clears temporary files and old Recycle Bin items automatically. CCleaner adds extras such as software updating and browser cleaning, which some people find useful.
References
Primary sources only: CCleaner’s own pages, regulators, courts and app stores. Each was checked on 7 Nov 2026.
- CCleaner (Gen Digital). End User License Agreement. ccleaner.com, checked 7 Nov 2026
- CCleaner (Gen Digital). Consent Policy, NaN Sep 2023. ccleaner.com, checked 7 Nov 2026
- CCleaner (Gen Digital). About CCleaner. ccleaner.com, checked 7 Nov 2026
- CCleaner (Gen Digital). Products Policy (product privacy notice), NaN Feb 2026. ccleaner.com, checked 7 Nov 2026
- Google Play. CCleaner – Phone Cleaner: Data safety. play.google.com, checked 7 Nov 2026
- US Federal Trade Commission. FTC Order Will Ban Avast from Selling Browsing Data for Advertising Purposes, Require It to Pay $16.5 Million, 22 Feb 2024. ftc.gov, checked 7 Nov 2026
- CCleaner (Piriform). Security Notification for CCleaner v5.33.6162 and CCleaner Cloud v1.07.3191 for 32-bit Windows users, 18 Sep 2017. ccleaner.com, checked 7 Nov 2026
- Microsoft Security Intelligence. PUA:Win32/PiriformBundler, 27 Jul 2020. microsoft.com, checked 7 Nov 2026
- CCleaner (Piriform). Reports of Windows Defender Classifying CCleaner as PUA, 6 Aug 2020. ccleaner.com, checked 7 Nov 2026
- CCleaner (Piriform). Update to the CCleaner v5.33.6162 and CCleaner Cloud v1.07.3191 Security Notification, 21 Sep 2017. ccleaner.com, checked 7 Nov 2026
- CCleaner (Gen Digital). Will CCleaner Pro Crack software help speed up your computer?. ccleaner.com, checked 7 Nov 2026
- Microsoft Support. Manage drive space with Storage Sense. support.microsoft.com, checked 7 Nov 2026