Ithaca Free Software GNU Linux

(Letter to the “PC World” editor)

False Fact Check

“Fact Check” by Robert Strohmeyer, PCW 7/08 pg. 117 “True or False: Linux Is Immune to Malware and Viruses” leaves the false impression that the main reason Linux is secure from viruses and malware is obscurity (few users). GNU/Linux (the more accurate name of Linux) security does not depend upon obscurity: few users or secret code. Semantic’s Ben Greenbaum’s is quoted in the article, “There is no technical reason that Linux would be immune to viruses …”. This is literally true, but semantically false in the impression it leaves. A full explanation of GNU/Linux security and comparison with Windows security is perhaps too lengthy to be published in “PCW Forum”, but I have published it at: http://ithacafreesoftware.org/forum/vie ... ?p=702#702 The bottom line is: Even when GNU/Linux achieves the market dominance Windows has had, viruses and malware will not be a significant problem. GNU/Linux is a very hostile environment for viruses and malware.

Eric Skalwold
Ithaca, NY

The facts about GNU/Linux security: Free Software with its open source code means that people the world over are looking for security holes and patching them constantly. Serious security issues are typically patched within a few hours to a day, and all major GNU/Linux distributions have patches out shortly thereafter. All major GNU/Linux distributions allow automatic security updates. If this feature is not activated a simple click when the update notice pops up takes care of security updates. Even minor security issues are addressed in a timely manner because they are important to someone. There is no waiting for Microsoft (or Apple) to get around to dealing with the problem months or years later... or never. The rapidity with which GNU/Linux programs are patched, with comparison to Windows programs, makes GNU/Linux computers inherently more secure. Furthermore, updating insecure software is much easier for a GNU/Linux user than for a Windows user. When a GNU/Linux user receives a security update for the distribution they are using, it is for all the programs on their computer regardless of who created the program. This is in stark contrast to the Windows world where each software company must supply their own patches and the user must somehow be aware they exist, and then go to multiple places to get all the patches.

Although there can be viruses on GNU/Linux systems, it is far less likely and there is far less possibility of them migrating the way they do on Windows OSes. Even when GNU/Linux grows to have the dominance Windows currently has, viruses and malware will not be the problem they are for Windows computers. GNU/Linux already has, or soon will have dominance,in the server, super computer, and embedded systems markets. GNU/Linux servers form the backbone of both the Internet and Google, and that makes GNU/Linux a target. GNU/Linux is not obscure.

Networking was an after thought for Window OSes. Contrast this to GNU/Linux. The nature of the GNU/Linux OS makes it difficult for viruses and malware to infect a machine, and even if this happens, it is even more difficult for the viruses or malware to spread to other GNU/Linux computers. Unix, and Unix like OSes including GNU/Linux, were designed as network OSes, and they provide for internal network security as well as external network security. The world has had over thirty years experience creating a more and more secure Unix and GNU/Linux environment. Microsoft has had since Windows 2000.

There are more than a dozen major GNU/Linux distributions, and many many more with smaller user bases. Some people, even some people influential in the GNU/Linux world, see the number of GNU/Linux distributions is as a problem: lack of consistency. Actually the lack of consistency is a strength of GNU/Linux for a number of reasons. Speaking only to the problem at hand; this lack of consistency creates huge problems for virus and malware writers. There are not just a large number of GNU/Linux distributions, there are many of versions of each distribution. This results in multiples of multiple binary codes. It is very hard to write binary only viruses and malware for GNU/Linux, and still harder to make them propagate.

Windows users are used to installing software by going to various web sites (some of them malicious web sites), and downloading and installing the program they find there "by hand", rather than getting their software from a unified central repository. GNU/Linux users typically get their software from the central repository of their distribution and that software is installed by the software package management application used by that GNU/Linux distribution (there are several different package management systems used by various GNU/Linux distributions). The security characteristics of using a built-in package manager are qualitatively different from installing software from an arbitrary web site.

The firm separation of User from administration makes it harder for viruses and malware to propagate on a GNU/Linux computer than on a Windows computer. What's more, the less experienced the GNU/Linux user is, the less likely they are to own any executable programs for a virus to infect. In the GNU/Linux world someone must own every file, be it data or executable program. Normally Root (administrative privileges) owns all executable programs, and User cannot write to any executable programs. A user would have to become Root and install the virus or malware. Again, the less experience the user, the less comfort with becoming Root. Windows users frequently use their computers with administrative privileges enabled which gives infecting viruses and malware administrative privileges. In the Windows world less experience results in more propagation of viruses and malware. In the GNU/Linux world less experience results in less propagation.

The inherent conservatism with which GNU/Linux networking programs have been written is becoming a standard part of all GNU/Linux programming. High level macros and other structures which have enabled Windows viruses to propagate so rapidly are not a part of GNU/Linux programs. Windows built-in firewall does not block outgoing connections. Even if a malicious piece of software is unable to gain administrative privileges on a Windows computer, nothing will stop it from setting up email and web services and otherwise continuing to try and pester other computers. GNU/Linux does not allow this.

For a computer virus or malware to propagate its rate of multiplication must exceed its rate of destruction. GNU/Linux provides a hostile environment where it is unlikely the world will ever see the kind of epidemics that have been seen in the Windows environment.

Finally, and perhaps the most significant reason viruses and malware will never be a significant problem in the GNU/Linux world is simply because the software has the Freedom and open source characteristics of Free Software. In the Free Software world there is an intimate connection between developers, package maintainers (packages are how a GNU/Linux distribution installs software on a computer), and system administrators. In the Windows world there is no one to complain to and have it do some good. In the GNU/Linux world a livid system administrator whose system has just been cracked can send their flame-laden email directly to a developer once s/he has found out who was to blame for their sixteen hour day of system recovery. In the GNU/Linux world you know exactly who to send that flaming email to, and it will actually do some good.


Thanks to the input of Marty W., Mitch W., Doc, Raju, and http://librenix.com/?inode=21

Hi Eric, your link http://librenix.com/?inode=21 doesn't work for me..

Hi Elena. I just checked the link and it worked. I don't know why it didn't work for you. Try again.