Proprietary Software Is Often Malware

Proprietary software, also called nonfree software, means software that doesn't respect users' freedom and community. A proprietary program puts its developer or owner in a position of power over its users. This power is in itself an injustice.

The point of this directory is to show by examples that the initial injustice of proprietary software often leads to further injustices: malicious functionalities.

Power corrupts; the proprietary program's developer is tempted to design the program to mistreat its users. (Software designed to function in a way that mistreats the user is called malware.) Of course, the developer usually does not do this out of malice, but rather to profit more at the users' expense. That does not make it any less nasty or more legitimate.

Yielding to that temptation has become ever more frequent; nowadays it is standard practice. Modern proprietary software is typically an opportunity to be tricked, harmed, bullied or swindled.

Online services are not released software, but in regard to all the bad aspects, using a service is equivalent to using a copy of released software. In particular, a service can be designed to mistreat the user, and many services do that. However, we do not list instances of malicious dis-services here, for two reasons. First, a service (whether malicious or not) is not a program that one could install a copy of, and there is no way at all for users to change it. Second, it is so obvious that a service can mistreat users if the owner wishes that we hardly need to prove it.

However, most online services require the user to run a nonfree app. The app is released software, so we do list malicious functionalities of these apps. Mistreatment by the service itself is imposed by use of the app, so sometimes we mention those mistreatments too—but we try to state explicitly what is done by the app and what is done by the dis-service.

When a web site provides access to a service, it very likely sends nonfree JavaScript software to execute in the user's browser. Such JavaScript code is released software, and it's morally equivalent to other nonfree apps. If it does malicious things, we want to mention them here.

When talking about mobile phones, we do list one other malicious characteristic, location tracking which is caused by the underlying radio system rather than by the specific software in them.

As of March 2025, the pages in this directory list around 600 instances of malicious functionalities (with more than 740 references to back them up), but there are surely thousands more we don't know about.

Ideally we would list every instance. If you come across an instance which we do not list, please write to webmasters@gnu.org to tell us about it. Please include a reference to a reputable article that describes the malicious behavior clearly; we won't list an item without documentation to point to.

If you want to be notified when we add new items or make other changes, subscribe to the mailing list <www-malware-commits@gnu.org>.

Injustices or techniques Products or companies
  1. Back door:  any feature of a program that enables someone who is not supposed to be in control of the computer where it is installed to send it commands.
  2. Digital restrictions management, or “DRM”:  functionalities designed to restrict what users can do with the data in their computers.
  3. Jail:  system that imposes censorship on application programs.
  4. Tether:  functionality that requires permanent (or very frequent) connection to a server.
  5. Tyrant:  system that rejects any operating system not “authorized” by the manufacturer.

Users of proprietary software are defenseless against these forms of mistreatment. The way to avoid them is by insisting on free (freedom-respecting) software. Since free software is controlled by its users, they have a pretty good defense against malicious software functionality.

Latest additions

  • 2023-12

    Bungie's Destiny 2 is plagued with two major flaws:

  • 2018-01

    Google's ad platform enabled advertisers to run cryptocurrency miner code on the computers of YouTube users through proprietary JavaScript. Some people noticed this, and the outrage made Google remove the miners, but the number of affected users was probably very high.

  • 2025-02

    Microsoft is shutting down Skype on May 5th, 2025. As with other tethered proprietary programs, users have to rely on servers that are controlled by the developer. When these servers shut down, the service disappears. Instead of migrating to the service that Microsoft suggests as a replacement, Skype users should regain control of their communications by switching to one that is based on free software. Jitsi Meet, for example, is appropriate for small video meetings. Anyone can set up a Jitsi server and let other people use it, and indeed many of these are available around the world.

  • 2025-02

    Outlook has become a “data collection and ad delivery service”. Since Outlook is now integrated with Microsoft “cloud” services, and doesn't support end-to-end encryption, the company has full access to users' emails, contacts, and calendar events. Microsoft may also retrieve credentials associated with any third-party services that are synchronized with Outlook. This trove of personal data enables Microsoft, as well as its commercial partners, to flood users with targeted ads, and possibly to train “artificial intelligences.” Even worse, this data is available to any government that can force Microsoft to hand it over.

  • 2024-11

    Ubisoft is facing a fraud lawsuit for shutting down the proprietary video game The Crew, which was tethered to its servers. As this game can't be played offline, people who used to think they owned a copy of it are now realizing they only bought a license that could be revoked at will by the developer.

    This is one more example of what tethering of a proprietary program leads to. If The Crew were free software, its users would be able to set up another server, and keep on playing.

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