This guide tracks privacy issues with antivirus software and is periodically updated with new information.
It goes without saying that reliable antivirus software plays a crucial role in IT security. As malware continues to become more sophisticated and prolific (more than 350,000 malware samples are released every single day), home users and business owners alike need to have protection in place to stop these modern digital threats.
However, antivirus products are not immune to privacy problems. While the antivirus industry is ostensibly on the side of good, many antivirus products behave in a way that infringes on users’ privacy. Whether they intercept web traffic, sell browser history data, or allow backdoor access to government agencies, many antivirus products are guilty of jeopardizing the very thing they are designed to protect: your data.
Here are five ways antivirus software may interfere with your privacy.
1. Selling your data to third-party advertisers
To provide you with the protection you need to keep your system safe, your antivirus software needs to know a lot about you. It keeps an eye on the programs you open to ensure you’re not accidentally executing malicious software, and it monitors your web traffic to stop you accessing dodgy websites that might try to steal your login credentials. It might even automatically take suspicious files it finds on your computer and upload them to a database for further analysis. This means your antivirus software could collect and process an awful lot of your personal data if it wanted to.
With great power comes great responsibility.
While some antivirus providers are quite conscientious with their users’ data and only use it when absolutely necessary, others are much less scrupulous.
AVG – A few years ago AVG came under fire when the company announced changes to its privacy policy that would allow it to sell its users’ search and browser history data to third parties (i.e. advertisers) in order to monetize its free antivirus software. Of course, AVG isn’t the only antivirus company to monetize its users’ data.
Avast – Avast’s popular free android app sends personally identifiable information such as your age, gender and other apps installed on your device to third-party advertisers. As an AVG spokesperson explained to Wired, “Many companies do this type of collection every day and do not tell their users.”
From free VPN services to free antivirus, the old adage rings true: if you’re not paying for the service, you’re probably the product.
2. Decrypting encrypted web traffic
Most modern antivirus products include some sort of browser protection that prevents you from accessing known phishing and malware-hosting websites. However, doing so is easier said than done due to the fact that so much data is now transferred via Hypertext Transfer Protocol Secure (HTTPS).
HTTPS is the protocol your web browser uses when communicating with websites. The “S” in HTTPS stands for “secure” and indicates that the data being sent over your connection is encrypted, which protects you against man-in-the-middle attacks and spoofing attempts. Today, 93 percent of all websites opened in Google Chrome are loaded over HTTPS, up from 65 percent in 2015. If you want to know if a website uses HTTPS, simply check the URL or look for a padlock icon in the address bar.
The rapid adoption of HTTPS has helped to make the web a more secure place, but it has also introduced an interesting problem for antivirus companies. Normally when you visit an HTTPS website, your browser checks the website’s SSL certificate to verify its authenticity. If everything checks out, a secure connection is established, your website loads, and you can browse away to your heart’s content, secure in the knowledge that the website is legitimate.
But there’s just one problem. Because the connection is encrypted, there’s ultimately no way for antivirus software to know if the website you are trying to visit is safe or malicious.
Most antivirus products use HTTPS interception to overcome this issue. This involves installing a local proxy server that creates fake SSL certificates. When you visit an HTTPS website, your connection is routed through your antivirus’ proxy server, which creates a new SSL certificate and checks the safety of the site you’re trying to access. If your antivirus software judges the website to be safe, the site loads as normal. If the website is unsafe, the proxy will display a warning in your browser.
By redirecting your data through a proxy, your antivirus is decrypting the data you send on encrypted connections – data that is only meant to be visible to you and the HTTPS website.
There are a few ramifications here:
- Because your antivirus is faking SSL certificates, there’s no way to be 100 percent certain that the website displayed in your browser is the real deal. In late 2017, Google Project Zero researcher Tavis Ormandy discovered a major bug in Kaspersky’s software. In order to decrypt traffic for inspection, Kaspersky was presenting its own security certificates as a trusted authority, despite the fact that the certificates were only protected with a 32-bit key and could be brute forced within seconds. This meant that all 400 million Kaspersky users were critically vulnerable to attack until the company patched the flaw.
- Most antivirus products query the safety of a URL server side, which means the company could potentially track your browsing habits if they wanted to.
- It increases the risk of phishing attacks and man-in-the-middle exploits.
A team of researchers even published a paper on the troubling security implications of HTTPS interception by popular antivirus companies, where they noted:
As a class, interception products [antivirus solutions that intercept HTTPS] drastically reduce connection security. Most concerningly, 62% of traffic that traverses a network middlebox has reduced security and 58% of middlebox connections have severe vulnerabilities. We investigated popular antivirus and corporate proxies, finding that nearly all reduce connection security and that many introduce vulnerabilities (e.g., fail to validate certificates). While the security community has long known that security products intercept connections, we have largely ignored the issue, believing that only a small fraction of connections are affected. However, we find that interception has become startlingly widespread and with worrying consequences.
VPN.ac examined the issue as well and discovered that antivirus suites carrying out HTTPS interception also break HTTP Public Key Pinning (HPKP):
HPKP is a technology enabling website operators to “remember” the public keys of SSL certificates in browsers, enforcing the use of specific public keys for specific websites. This reduces the risk of MiTM attacks using rogue/non authorized SSL certificates. But HTTPS scanning and HPKP can’t work together, therefore if a website has HPKP enabled, when you access it the support for HPKP for that site will be disabled in the browser.
VPN.ac found this to be the case with ESET, Kaspersky, and Bitdefender:
Tip: Avoid antivirus software that utilizes HTTPS interception/scanning, or just disable this “feature” within your antivirus.
3. Installing potentially unwanted programs on your computer
Even if your antivirus doesn’t pose a direct threat to your privacy, it may come bundled with software that does. As the name suggests, potentially unwanted programs, or PUPs for short, are applications that you may not want on your computer for various reasons.
While they’re technically not malicious, they usually change the user experience in some way that is undesirable, whether that’s displaying advertisements, switching your default search engine, or hogging system resources.
Many free antivirus products come with PUPs such as browser toolbars, adware, and plugins that you may inadvertently allow to be installed while quickly clicking through the installation process.
For example, free versions of Avast and Comodo try to install their own Chromium-based web browsers, which you may or may not want on your computer. Meanwhile, AVG AntiVirus Free automatically installs SafePrice, a browser extension that claims to be able to help you find the best prices while shopping online. Unfortunately, it can also read and change all your data on the websites you visit.
A few years back Emsisoft found that most free antivirus suites were bundled with PUPs. Here were the culprits:
- Comodo AV Free
- Avast Free
- Panda AV Free
- AdAware Free
- Avira Free
- ZoneAlarm Free Antivirus + Firewall
- AVG Free
PUPs aren’t inherently malicious, but they can seriously encroach on your privacy. Some PUPs will track your search history or browser behavior and sell the data to third parties, while others may compromise your system’s security, affect system performance, and hinder productivity. Keep unwanted applications off of your computer by carefully reading installation options during the setup process and only install the software and features that you need.
4. Cooperating with governments
It’s theoretically possible that antivirus software could be leveraged to help government agencies collect information on users. Most security software has very high access privileges and can see everything that’s stored on a computer, which is necessary in order for the software to keep the system to safe. It’s easy to see how this power could be used by nefarious parties to spy on individuals, businesses, and governments.
Kaspersky Lab, a Russia-based cybersecurity company whose products account for about 5.5 percent of antivirus software products worldwide, was embroiled in a major privacy scandal a couple of years ago. According to the Washington Post, Kaspersky software used a tool that was primarily for protecting users’ computers, but also could be manipulated to collect information not related to malware. Kaspersky is the only major antivirus company that routes its data through Russian Internet service providers, which are subject to Russia’s surveillance system.
In September 2017, the U.S. government banned federal agencies from using Kaspersky Labs software following allegations about cooperation between Kaspersky and Russian intelligence agencies. Shortly after, the FBI began pressuring retailers in the private sector to stop selling Kaspersky products, and the British government issued a warning to government departments about the security risks of using Kaspersky software.
Of course, it would be naive to think this issue is limited to Russian software. Similar concerns have been raised recently about Huawei equipment with “hidden backdoors” installed.
“Antivirus is the ultimate back door,” explained Blake Darché, a former N.S.A. operator and co-founder of Area 1 Security, as quoted by The New York Times. “It provides consistent, reliable and remote access that can be used for any purpose, from launching a destructive attack to conducting espionage on thousands or even millions of users.”
5. Undermining security and giving hackers access to private data
Sometimes, security software does the opposite of its desired intent by undermining your security.
One such case occurred with the Royal Bank of Scotland (RBS), which was offering Thor Foresight Enterprise to its business banking customers. In March 2019, Pen Test Partners discovered an “extremely serious” security flaw with the software that left RBS customers vulnerable:
Security Researcher Ken Munro told the BBC: “We were able to gain access to a victim’s computer very easily. Attackers could have had complete control of that person’s emails, internet history and bank details.”
“To do this we had to intercept the user’s internet traffic but that is quite simple to do when you consider the unsecured public wi-fi out there, and it’s often all too easy to compromise home wi-fi set ups.
“Heimdal Thor is security software that runs at a high level of privilege on a user’s machine. It’s essential that it is held to the highest possible standards. We feel they have fallen far short.”
While Heimdal was quick to patch the vulnerability within a few days, it does raise an interesting point. That is when your security software is actually undermining your security.
Choose your antivirus software wisely
In the best case scenario, antivirus companies use your data responsibly to refine their products and provide you with the best malware protection possible.
In the worst case scenario, they sell your data to third-party advertisers, install annoying software on your system, and cooperate with government agencies to spy on your personal information.
So, how do you sort the best from the rest?
- Pay for your antivirus software. Most free antivirus products will be far more liberal with your data than premium software as the company ultimately needs to monetize their services in some way.
- Read the end user license agreement. Know what you’re getting yourself into before you install the product. Take a moment to read the license agreement and/or the company’s privacy policy to find out what the organization intends to do with your data.
- Read installation options: It’s easy to blindly click through “Next” when installing new software. This can result in the installation of browser toolbars, adware, and all sorts of other PUPs, which can encroach on your privacy in various ways.
- Customize privacy settings. Some antivirus software will allow you to customize privacy settings such as usage statistics, browsing behavior, and whether to upload malicious files for analysis. Adjust these settings to maximize your privacy.
- Read AV reports. Some independent analysts release reports on how antivirus companies handle your data. Take the time to read these reports and reviews to get a better understanding of a company’s reputation and how it handles privacy matters.
It’s important to note that this article isn’t a rallying call to abandon all antivirus software in the name of privacy, because there are some good players out there.
Antivirus software is an essential part of modern IT security and plays a critical role in protecting your data against malware, phishing, and a plethora of other digital attacks that pose a real threat to everyday users.
While some antivirus providers are invasive and should be avoided, there are still some companies that strive to protect their users’ privacy. Emsisoft, for example, has earned itself a reputation for providing reliable protection without compromising its users’ privacy. ClamAV is another privacy-friendly option that is completely open source.
So do your homework, weigh up your options carefully and remember that not all antivirus solutions are created equal when it comes to respecting your privacy.
Antivirus software is also being used to censor websites that don’t support the official government narrative. And when I tried to dispute the way Norton categorized a certain website I got an error message, “we are unable to process your request.” How do we find antivirus software that doesn’t support fascism?
So, what do we use now then?
For antivirus, which deosnt collect ip address or data?
don’t really know anymore, even webroot makes it imperative that they are collecting and using your cookies their way and if you are not fine with this stop using their software…ah duh, i just paid for it. they are working with the fbi and collecting data from everyone
even that clamav, the immunet one has real time protection, very light. But its cisco base.
G data doesnt sell to 3rd party tho. But they collect some some
Emisoft also collects ip addy. If reading through privacy policy.
This is an excellent article.
Also, do leave the political hysteria alone: Kaspersky is just another commercial enterprise that is no worse than any Eastern or Western-based software companies in general. Kaspersky isn’t out there to serve your privacy on a golden platter to KGB or whatever. Watch and read less psychotic political propaganda and your ability for critical thinking will be back in no time.
Thank you, Comrade. Nothing to see here – Don’t fear Russian bear!
Guys, Sven, PLEASE Make a review of Avira Phantom VPN.
It’s such a disaster!
While using Avira Phantom VPN, websites are redirected to a Russian phishing link.
You can’t believe it, this VPN promises: “Ultra-secure: Top, Bank-Grade Encryption” (you can read it on Avira Phantom VPN website). I changed VPN and then no redirects were anymore.
I am curious what your results will be.
Some strange connection with Russia, or redirecting to the Russian Phishings websites, appears regularly by Avira Phantom VPN, but Avira says they are from Germany..
Best regards
I just downloaded ClamAVNet for Mac OS. I was surprised to find that it’s not in my App Folder. Reading the documentation, I see that it’s a command line (Terminal) accessed program. And there were additional steps involved in activating the software–including removing and adding command line inputs. Even after following their documentation instructions, I still get error messages (directories not writable by me, my machine’s admin) and can’t use the software. And yes, I have Homebrew installed on my machine. This is why so many people use GUI version software. I realize many tech aficionados prefer command-line interaction, but many of us don’t want to waste hours learning about each software we download just to use our machines. We already have exhausting jobs and just want our machines to work.
I read through the TOS and PP of BitDefender & Norton AV and was repulsed they collect so much personal info and have such a deep level access to our machines and data. The other privacy-respecting option mentioned in this article, EmsiSoft, is available only for Windows. So I guess that leaves me without AV protection since I can’t figure out how to get ClamAVNet to work. Ironically, their website claims their main goal is to make AV “easy” for the average person. HA!
I recently theorized the threat & possibility of “man in the middle” with those antivir certs after i came across the cert issues people had reported on a forum. Did a search and found your page about it too. I agree, its a security issue and can be used for snooping (its already used for that most likely). But for most people, they have no security issues to hide on that level really, its of no real concern to them, but yeah definately a potential privacy intrusion annoyance.
[I haven’t had any antivir installed on any of my systems in the last 10 years (I use my own special methods, and only install antivir/antitrojan for removing stuff if I catch something I can’t manually disassemble/unarm for my own curiosity (then uninstall). A year ago, I installed an antivir to checkup for fun (curious after 3 years with sensing no problems by my daily usage). But it found nothing! Got kinda annoyed & bored that there was nothing new & juicy to research/pry into (lol zzz).]
Telling people to pay for their AV is foolish. That’s like saying pay more for a diamond or house, because that means it will be better. That is not necessarily so. Like you said elsewhere, READ THE AGREEMENT. If the agreement for the paid version offers more privacy than the free version, then MAYBE the paid version is worth it.
If you select Settings > Network settings > Encrypted connection scanning > Do not scan encrypted connections > Save, in a Kaspersky Lab Product, Safe Money will be disabled.
https://twitter.com/doctorow/status/1478479483585933312
As if it doesn’t get worse, Norton now deals on crypto. Luckily it’s an opt-in, not opt-out, but this is unethical and not financially worthy in that Norton gets 15% cut while you pay for electricity to mine, of which your 85% cut likely would not cover for.
I have discovered that some AV/Malware solutions also targets assumed copyright infringement files like video files without warning.
That doesn’t have anything at all to do with my security, so that’s really dirty – and what if the routine they use goes sour and makes a false positive and wipes something that I have created myself?
Just discovered that System1 owns TotalAV, Startpage, Waterfox and a collection of other things I haven’t heard of. Check it out at https://system1.com/what-we-do#brands.
Hi Sven,
thanks a lot for your article. Great job doing awareness about the privacy concerns on the antivirus.
Just one amend to the article, related to the second point “2. Decrypting encrypted web traffic” just to comment that HPKP is deprecated on behalf of Certificate transparency, so it is not used anymore.
I don’t know if Certificate Transparency is also affected, but at least, you should remove this part from point 2.
Kind regards and thank you again for your work.
Hi Sven,
Very informative and much needed article. Thank you for writing this.
You stated in the comments how privacy on Android was a joke. I’d like to know which phone you use with which operating system? As far as I’m aware, Apple is no better. So the only other viable option is Lineage on Android. Is this correct?
Many thanks
I do not use a phone very often and simply do not spend much time trying to figure out how to have more privacy on phones. I’m just not someone that spends much time on a phone, outside of phone calls, which obviously are not private anyway. Privacy on a phone is extremely challenging, as we covered in:
Controlling Communication Channels
How to Really Be Anonymous Online
Well it’s been a while since I commented here, but I’ve been reading regularly.
The best two mobile OS right now (IMHO) are GrapheneOS & CalyxOS, they are both built on Android. For security/privacy, GrapheneOS is marginally ahead, but CalyxOS is more “normie” friendly, as you can install the regular Google Play apps you might be used to.
However, since the hardware itself that these two options are based on (Google Pixel Phones), that may be offputting for privacy die-hards. The problem is though, is that Pinephone & Librem5 are difficult to get, Librem5 or Librem5 USA hasn’t shipped for months & Pinephone…you’re essentially a beta tester using a cheap Chinese phone, that is based on hardware that’s years old. You’re not going to attract the masses with that.
I think more will become available, there’s a budding industry for such users.
Hi Richard, good to see you back! It’s been a while.
Indeed! I keep an eye & have shared this site with others. I hope your revenues are up & so are your site regulars.
Hi Sven,
I have heard that ClamAV is very good. My concern is that it does not do real-time scanning (prevents attackers entering). I have also heard that ClamAV does not scan memory.
Is this true and if so should this be of concern?
Regards,
BoBeX
Hi BoBeX, I have not tested ClamAV and do not know.
Hi Sven,
Kaspersky has caused me several concerns.
The first was the persistent recommendations that there is some threat and to upgrade to there paid service. These would come in the form of your email address has been compromised; but they actually offer no information that was not already available on “haveibeenpwnd.com.” (Not my email but family members machines that I had installed the product on)
Secondly, (after an update – in the last three months) Kaspersky were advising of compromised email addresses but these addresses were not specific to the machine or the Kaspersky account; rather, they were of other family members. So Kaspersky was advising a user that “your” (though it was not the correct account) email has been compromised. The advised me incorrectly that “my” email account (not my email account – a family members) has been compromised (Again known from haveibeenpwnd.com). This family member has had no access to my machine or accounts – the same family member is not at all a Kaspersky user; however they are clearly correlating people in my social network.
Thirdly, I contacted Kaspersky about this concern; however their complaint web-form had a very short character limit so I sent them my email address stating that I wished to make a complaint and they did not respond.
Fourthly, I changed my DNS provider to OpenDNS recently and in the information provided to me on what a site would look like, what an error message would say if they had blocked a malicious site. The error message occurs and looks exactly like what was shown; accept, it says blocked by Kaspersky. It appears they are intercepting the page and modifying the content.
Fifthly, Kaspersky is no sending me messages stating, we have detected x amount (say 4000) web trackers. They have only started sending me this message since I changed my DNS provider (Browser based extensions did not trigger this change – it appears clear it was the DNS provider change) (I do not always use a VPN – any of my google accounts or my password manager start complaining when I am not located where they think I should be – probably a good thing)
Kaspersky is monitoring and intercepting a lot if not all of my traffic and I am unhappy with how the use my data. Their hysterics has a great reputation (I do not know if this is warranted) but for me they completely fail on every other account.
I believe they are unethical and possibly use some predatory looking practices.
Regards,
BoBeX
I suggest you should disable Kaspersky’s web antivirus component so that it wont scan your web traffic and modify web content & even its mail antivirus can also be a threat to privacy disabling that is also preferable.
can you review more antivirus products so we have a better idea of what to choose? things like clamav and emsisoft are definitely not the highest rated antivirus programs last I checked. there is also the question on whether or not you can have multiple antivirus programs without hurting the computer or causing conflicts or whatever… is malwarebytes good or a scam? do you use emsisoft? do you use clamav? do you use windows defender? is windows defender spying on us? is bitdefender spying on us? is malwarebytes spying on us? what program should we pay for?
also, a lot of antivirus companies now offer vpn services, such as avast vpn. I presume you want us to stay far away from them?
We don’t get too involved in antivirus solutions here. If you are still on Windows, then the built-in antivirus is more than sufficient, and if you are on Linux or Mac OS, I think you can skip the antivirus and just use common sense, good blocking tools (such as an ad blocker, tracker blocker, malware domain blocker, etc.) and if you see a suspicious link or file, run it through VirusTotal.
Sven. Just a question regarding HTTPS interception as mentioned above and used by certain Antivirus suppliers, and found by VPN.ac. Are we wanting to have both lines green, or both red?
Thanks for your great work, and I am .giving friends a link to your website
If the americans accused Kaspersky of collusion with the Russian government then you can bet that the American government is in bed with AV companies in the US and allied countries. They ddin’t object to Kaspersky’s activities in the name of protectin privacy, but only because their own privacy was compromised. The US government has shown it has absolute contempt for the privacy of its citizens and people worldwide and it has also demonstrated a desire to collect as much information about as many people as possible. Information is power after all. It is extremely naive to think that the US agencies are not taking as full advantage as they possibly can of the high level of access that AV companies have to the personal data and activities of private individuals, companies and other countires. I would even go as far as to say that the vast expansion of AV programs in recent years, in terms of the software they run on your computer and the activities of yours that they monitor, only makes sense as a response to the desire to surveille you rather than protect you.
Hi Sven,
I installed Emsisoft on my SmartPhone. The first thing I’m asked for is to login with Google!
Reading your article that cannot be a good sign, or am I wrong. I believe that ClamAV is not good to protect your device, but is only good to clean an infected one. What privacy friendly reliable AV for Android do you suggest? Bitdefender, Sophos….?
I still think Emsisoft is the best all-around option. I’ve never tried it on Android, but expecting anything to be private on Android is a joke to be honest. It’s like privacy at an airport.
Hi Sven,
Emsisoft for Android consists 4 inbuilt trackers that means leak of privacy. Only one Android antivirus that I found free of trackers is ESET. Please correct me if I’m wrong but each tracker is a broken privacy issue. It is same for Android browsers – full of trackers up to 9 in Opera. But there are still existing without.
I read the terms and conditions of Emsisoft Mobile Security and if the law asks for user information they will collaborate
Every business MUST follow the laws in the legal jurisdiction in which the business operates. There’s no getting around this fact and it applies to all businesses in all locations. However, if Emsisoft is not collecting extensive data, there is very little to hand over. This happens with good no-logs VPNs.