CCleaner may be installing Avast anti-virus without your permission

David Matthews

Posts: 437   +88
Staff member
Facepalm: Many users of popular system cleaning app, CCleaner, have complained that installing the software also installs the Avast anti-virus program without their permission. We have confirmed those claims.

Ever since Avast acquired Piriform, the maker of CCleaner, there has been a steady stream of disappointment from a user base that once totaled around 130 million people. Reports have been coming in that CCleaner will install the Avast anti-virus software without permission. This is troubling indeed.

Starting with version 5.37 of CCleaner, released this past August, Avast was bundled as an optional add-on. Normally, this is supposed to be opt-out with a checkbox at the bottom verifying that the user wants to include Avast in the CCleaner installation. However, many users are saying that it's anything but opt-out.

Frustrated users have complained on Avast's forums about the hidden installation:

"This happened to me today when updating CCleaner Free to v5.40. Did not notice any bundled offers, and I am always on the lookout for them. Always use advanced install options too."

"It happened to me too. ccleaner 5.43 installed avast without consent. There was no option to opt out of avast installation."

"It auto installed Avast without consent and no opt out. There was no check box on the setup page to opt out of installation!!!!! You guys should be ashamed to do this kind of business. When will you realize that people you FORCE your product into like this are less likely going to buy your product, or do some good publicity about it ??? All the contrary!"

A product manager for CCleaner responded to the complaints by reiterating that the Avast installations are supposed to be completely optional and users should "always see the consent screen" whenever they install CCleaner Free edition or Pro Trial. However, the product manager did acknowledge that there were people who were experiencing problems:

We are monitoring a small number of edge cases where it seems the consent checkbox is not displaying correctly. After gathering what information we could from our users on the CCleaner forums, we were able to identify a case where high system load could delay the offer from displaying immediately. This allowed us to reproduce the issue internally and resolve it. We made change to guard against this root cause and released it in v5.39 (January 16th). There is potential for another bug/edge case to be causing the consent checkbox to not be visible, and this is what I would like to continue to investigate with your assistance.

However, when we tested the latest version of CCleaner today, we were never prompted about the Avast installation and surprise, surprise, our system suddenly had a new antivirus installed that we did not consent to.

CCleaner offering bundled third-party software isn't new. The installation has previously promoted Google products like Chrome and Google Drive as well as Skype and Dropbox. However, this recent Avast bundle is especially ironic because Avast is supposed to be a cybersecurity company that prevents software from installing without the user's permission.

Avast posted a follow-up support article last Thursday explaining that Avast is not offered during every CCleaner install. If the user had previously unchecked the box to install Avast, it won't ask to install. As user APMichael explains, This is likely due to an entry in the Windows registry with the key "HKEY_CURRENT_USER\Software\AvastAdSDK\". If the value "LastOffer" is deleted then the Avast offer comes back.

This isn't the first controversy surround CCleaner. The Floxif malware was discovered in certain versions of CCleaner in late 2017. Back in August, Avast faced backlash over the removal of privacy settings in the free version and other spyware-like tactics.

For our part, TechSpot has updated the CCleaner entry in our downloads section to include the note about the unwanted Avast installation, which we consider a disgusting practice. We've also made the Portable and Slim versions the default downloads as we verified those two do not bundle any software. Finally, we'd point you to our article about the best alternatives to CCleaner considering the waning trust in Avast. While CCleaner is still a good product overall, we wouldn't blame you for choosing another product.

Permalink to story.

 
I've given up on both Avast and Ccleaner due to their increasingly shady practices. To be completely honest, Windows Defender combined with some good anti-spying browser extensions (Ublock Origin, for example) is enough protection for the typical Internet user. For anyone else I'd recommend Eset products such as NOD32 or possibly Bitdefender. Most other antivirus and internet security suites, particularly Avast and AVG, now spy on you almost as much as the things their supposed to protect you against! You have to dig through the settings to find all the inexcusable marketing and spying, which is all enabled by default. Even after turning that s**t off their still collecting *some* data, however. If you do go with the combo I mentioned (WD + extensions) be aware that Windows 10 itself is a massive data collection engine. If you want to minimize the amount of corporate data scraping on your system you should really use either Windows 7, Linux or a Mac.
 
Avast Antivirus v18 also updates CCleaner to the latest malware version

I am running CCleaner v5.20 and it's not easy to do so

If I download and install the full version of Avast Antivirus (v18), it automagically updates CCleaner v5.20 to the newest malware version even though updates are turned OFF and CCleaner is blocked in the Firewall (Glasswire)

To keep CCleaner v5.20, I install Avast v17 and then run CCleaner with updates turned OFF, Monitoring turned OFF and the Piriform & CCleaner cookies deleted in CCleaner.

Upon 1st Internet connection, CCleaner v5.20 is blocked in the Firewall before updating Avast to v18

Updating to Avast v18 from v17 will not update CCleaner if you do it correctly, but if you install Avast v18 completely instead of updating from v17, CCleaner will be updated to the malware version

These unfortunately are not the only problems with CCleaner and Avast....
Have you also noticed the newer versions permanently bypassing your firewall rules?

Bad Bad Stuff indeed!
 
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Ccleaner and its parent company Avast should be fined so that this shady practice is never repeated again.
I use Avast antivirus free edition but with most people I do not want something that is forced.
 
Resigned from Avast some 4 years ago because It obviously has becoming a mal/nag-ware. I'm on Win7 so I've decided to use external AV - Panda. But I read that with Spyware 10 You don't need no external AV. M$ Defender is enough.
 
I once had a higher opinion for Avast, back before they bought out AVG. Now my opinion for AVG has rubbed off on Avast. And now that same opinion is getting smeared all over CCleaner. I still use CCleaner. But I can not ignore all this bad press for the application.

Agreed. I purchased the pro version awhile back but now I'm considering looking to other products.
 
I've given up on both Avast and Ccleaner due to their increasingly shady practices. To be completely honest, Windows Defender combined with some good anti-spying browser extensions (Ublock Origin, for example) is enough protection for the typical Internet user. For anyone else I'd recommend Eset products such as NOD32 or possibly Bitdefender. Most other antivirus and internet security suites, particularly Avast and AVG, now spy on you almost as much as the things their supposed to protect you against! You have to dig through the settings to find all the inexcusable marketing and spying, which is all enabled by default. Even after turning that s**t off their still collecting *some* data, however. If you do go with the combo I mentioned (WD + extensions) be aware that Windows 10 itself is a massive data collection engine. If you want to minimize the amount of corporate data scraping on your system you should really use either Windows 7, Linux or a Mac.

Same here! Only suckers need anti virus due from lack of commonsense. 20+ Years only got one virus and that was Windows98SE and I was a kid/ young teen.
 
Seems about right considering how Avast quality has gone downhill and we get banner ads all the time for purchasing addons like Grimefighter or Driver updater.

I still have Avast in some of my systems but now am progressvely moving towards Bitdefender and its a delight. Never even notice that its there and It Just Works.
 
I removed Avast from my PC a few months ago because I was tired of the nag/scare screens. I have installed it on a couple of remote family computers but am going to be uninstalling it from those as well. I'm considering BitDefender for those.
 
For our part, TechSpot has updated the CCleaner entry in our downloads section to include the note about the unwanted Avast installation, which we consider a disgusting practice.
@David Matthews

For my part, I really hate to go here because I have enjoyed TechSpot for many years now.

In my opinion, if TS really considers this a disgusting practice, TS would remove CCleaner entirely from the download section. Not everyone reads every warning about what might be contained in the download. It is easy to play the blame game and blame anyone downloading it and getting something that they did not bargain for by saying something to the effect that "the warning is in our notice," however, I consider that displaced responsibility. People trust TS, however, this, as I see it, places that trust in question.

To me, leaving the product in the TS downloads is a tacit acceptance of the practice even though TS considers the practice disgusting. Companies that engage in such practices may, or may not, for that matter, pay attention if leading sites like TS take them to task by removing such downloads. The voice of TS against such practices would be emphasized significantly with the complete removal of all CCleaner downloads.

I get it is potentially useful software, but what else might be hidden? Right now, I am seeing CCleaner engaging in practices that are similar to the most egregious of those of fakebook.
 
I still use CCleaner but have stopped recommending it after the hidden malware episode. It is still better at removing unnecessary files than alternatives and has a the nice "deactivate" option available when handling start-up programs. It is also easier to use for the uninstaller than the one built into windows - which is useful when removing unwanted avast installs......
Updating anything these days is a balance of risk so keep your eyes open and don't be an unwitting alpha tester.....
 
5.51 here and don't see anything related to Avast. Is this regional, a test, or only on certain versions of Windows?
/W10 insider build 18305
//Will be back later today with info if I see this on my other PCs(7 and 10(non insider))
 
For our part, TechSpot has updated the CCleaner entry in our downloads section to include the note about the unwanted Avast installation, which we consider a disgusting practice.
@David Matthews

For my part, I really hate to go here because I have enjoyed TechSpot for many years now.

In my opinion, if TS really considers this a disgusting practice, TS would remove CCleaner entirely from the download section. Not everyone reads every warning about what might be contained in the download. It is easy to play the blame game and blame anyone downloading it and getting something that they did not bargain for by saying something to the effect that "the warning is in our notice," however, I consider that displaced responsibility. People trust TS, however, this, as I see it, places that trust in question.

To me, leaving the product in the TS downloads is a tacit acceptance of the practice even though TS considers the practice disgusting. Companies that engage in such practices may, or may not, for that matter, pay attention if leading sites like TS take them to task by removing such downloads. The voice of TS against such practices would be emphasized significantly with the complete removal of all CCleaner downloads.

I get it is potentially useful software, but what else might be hidden? Right now, I am seeing CCleaner engaging in practices that are similar to the most egregious of those of fakebook.

Understood and you make a good point. However, per the article, we have tested the Portable and Slim versions which do NOT contain Avast. We made those the default downloads so that even if people didn't necessarily read through the install, they wouldn't have to worry about Avast secretly installing anyway.
 
I can confirm that they are indeed installing avast without permission and it gives problems to remove avast and I just gave up on ccleaner because of that.
 
A lot of legit software has been doing this now. Avast was once voted the best free AV and now it's annoying as hell so got rid of it and paid for an av. CCleaner is my install, use, then remove software as it is still useful.
 
To those keeping CCleaner for its "uninstall" feature... I use the free version of RevoUninstaller for this. I bought Revo Pro since the product is so good, but stay with the freeware as it's easier to move, maintain etc. and does all I need. Try that.
 
To defeat anything unusual done by the regular CCleaner installer, I simply download the portable version and then copy the current executable version, either x64 or x86, into the folder where the software is installed. A vast problem can be solved in this way.

In dealing with my clients now, I am more circumspect. I download the portable version, install it manually, but do not give my clients obvious access to it. This keeps the Avast nagware away and still gives me the opportunity to do a needed cleanup of files. Otherwise, I end up with too many questions about Avast. Surprise!

Avast does something pretty underhanded with the CCleaner installer. Instead of presenting you with an obvious choice to install Avast or not in the first menu when you run the installer, you have to drill down and UN-check the Avast install choice. Many people do not pay attention and install Avast unknowingly.
 
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I've given up on both Avast and Ccleaner due to their increasingly shady practices. To be completely honest, Windows Defender combined with some good anti-spying browser extensions (Ublock Origin, for example) is enough protection for the typical Internet user. For anyone else I'd recommend Eset products such as NOD32 or possibly Bitdefender. Most other antivirus and internet security suites, particularly Avast and AVG, now spy on you almost as much as the things their supposed to protect you against! You have to dig through the settings to find all the inexcusable marketing and spying, which is all enabled by default. Even after turning that s**t off their still collecting *some* data, however. If you do go with the combo I mentioned (WD + extensions) be aware that Windows 10 itself is a massive data collection engine. If you want to minimize the amount of corporate data scraping on your system you should really use either Windows 7, Linux or a Mac.
Ok. So just who are you, and just why is yur advice so much wiser than my 40+ years of programming, coding, and repairing computers, starting with old Univacs?
 
For about a year I haven't been able to use ccleaner other than for registry as it kills passwords and sign ins no matter what I do. I get sick of these companies slipping in garbage I don't want. Auslogic just put in chrome I didn't want and also made it the default. Malwarebytes kills my auslogic install sometimes. I appreciate "free" (although there are tradeoffs for free), but if you have to be underhanded or sneaky just stop giving us this stuff "free". They keep changing how you install to stop their manipulations and even if you select for no changes it may do things anyway. And how about the constant updated version garbage. I doubt these are really updates it is just to have you do a fresh install to facilitate their attempts at slipping in junk.
 
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