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How to Write a Linux Virus in 5 Easy Steps

It's easy for people to pick at Windows for being prone to virus and malware attacks. It's almost a given belief that if you're running a PC with a Windows operating system, you're much more susceptible to attacks than users with other operating systems.

But let's quickly look at the reasons for this. First, it isn't really Microsoft's fault. It isn't that Windows is technically inferior, it's that the majority of the world runs on Windows. This fact alone is very attractive for any virus coder or exploiter. As a virus writer, you'd want to attack the majority, not the minority.

Secondly, because the vast majority of the world's computers runs on Windows, everyone from very tech savvy users to the greenest of novices is included in this pool. There are many who are just not as educated--for various reasons--about software and Internet safety. So here we have a huge pool of people, many of which aren't informed. These are two main reasons why a Windows desktop is the prime target for attacks.

In recent years however, the popularity of the Linux operating system has shot up tremendously. Ubuntu for example, is a favorite among enthusiasts. Linux is revered for many industrial strengths, but it too has security issues. A Linux computer that's improperly configured, can also take a beating from malware, hackers, and the like. Thankfully, popular builds like those from Ubuntu, are distributed pre-locked down. At the local environment however, Linux is by nature, significantly stronger than Windows in terms of user and multi-user security.

Despite its strong underpinnings, Linux has become too popular to ignore. Now, a blogger by the name of "foobar" has written a guide on how to efficiently infect a Linux user's system, stating even not to "underestimate the ignorance of a Linux user." A snippet from foobar's guide:

There is this rumor going around that Linux is virus free. It is said that the old-fashioned multi-user heritage of Linux (and other *nix OSs) prevents malware, since users are not normally running their programs in admin mode (as root user). We are reminded that execute bits are needed to run anything – contrary to Windows – and that execute bits aren't set on any attachments or files saved from emails or from a web-browser.Therefore, we are told, the very architecture of Linux is so much more superior to Windows that it's just not possible to successfully spread malware. Of course – it is acknowledged – a low-level bug, a buffer overflow or other issue is exploitable. But nevertheless, users can't just catch a virus by email or downloading malware from the Internet, contrary to “those Windows users”. Linux will protect them from their own stupidity.

foobar is setting out to prove that Linux is no more secure to malware than Windows is. Despite writing up the how-to guide on writing a virus for Linux, foobar doesn't actually point out the actual malware coding part, and instead instructs a would-be malware coder on how to infect a Linux system.

In a related playing field, Apple is famous for claiming that its computers are bullet proof from malware and viruses too, often indicating so in advertisements that show how "sick" a PC can get versus a Mac. Because of its relatively low usage rate compared to Windows computers, Macs have traditionally been more secure only because no one really wanted to spend time to attack a small minority group. The landscape however, is changing too for Macs. With popularity increasing, viruses and attacks are becoming more popular, with the most recent infection spreading through a torrent of Apple's iWork '09 office suite.

Do you believe that the security of a system lies on the technical aspects of the operating system in use? Or do you firmly believe that the security lies soley on the sholders of the user? Do you think foobar's claims are correct?

  • jsloan
    oh, poor babies, welcome to the real virus ridden world.
    Reply
  • tipoo
    As a vrius writer, i'm offended at being included in an article about viruses!


    lol, more typo's.
    Reply
  • ogre9001
    To all of the brilliant Linux virus writers....Why is it that you keep making these claims, but nothing ever comes of them?
    I have read for the past decade about all of these threats that will show linux to be just as vulnerable as windows to viruses.
    Did I miss some news?
    I don't remember hearing about the massive virus attack that took down thousands of linux servers and turned linux workstations into spambot networks numbering in the hundreds of thousands.
    I look at this the same as I look at the annual threat of an attack that will completely lock down the internet.
    Deleted by Moderator
    Reply
  • echdskech
    from the linked article:

    f course, that also means that the mail attachment will have this extension as well. Some users may notice, many others will not.

    This type of malware doesn't exploit the OS so much as it does the user's intelligence. As we all know, no matter how id10t-proof we make systems, someone just builds a better id10t.

    Ofcourse, maybe the reason for Linux's reputation of security comes as much from the min IQ requirement of using 'ye olde Linux arcane distros as it is in the OS design. Recent distros are becoming more and more user friendly and therefore lowering aforementioned requirement.

    I suppose it is a necessary evil if it ever hopes to appeal to as broad an audience as Windows. I just hope the dev guys can keep up to prevent it from being a cesspool. =/
    Reply
  • batkerson
    I sincerely believe that the security any computer system is primarily the responsibility -- i.e., the result of design and implementation -- of the OS. The dept. of justice dropped the ball a few years back when, ultimately, it did not require the breakup of MS into operating system and applications companies. If MS truly would concentrate on the efficiency, and security, of the OS rather than on bells and whistles that few people need and even fewer actually want, then, oh, what a Windows we would (probably) have. MS is so intent on adding "functionality" or appearance that their security division (or whatever it's called internally) has a moving target to protect. To MS: stop adding functionality for an OS cycle or two and pour all your money into efficiency and security THEN, when the OS is ready, move forward with the other "stuff".

    My 2 cents.
    Reply
  • eddieroolz
    batkersonI sincerely believe that the security any computer system is primarily the responsibility -- i.e., the result of design and implementation -- of the OS. The dept. of justice dropped the ball a few years back when, ultimately, it did not require the breakup of MS into operating system and applications companies. If MS truly would concentrate on the efficiency, and security, of the OS rather than on bells and whistles that few people need and even fewer actually want, then, oh, what a Windows we would (probably) have. MS is so intent on adding "functionality" or appearance that their security division (or whatever it's called internally) has a moving target to protect. To MS: stop adding functionality for an OS cycle or two and pour all your money into efficiency and security THEN, when the OS is ready, move forward with the other "stuff".My 2 cents.
    Splitting Microsoft wouldn't change anything. Besides, by having it together, it would actually offer them better interoperability and releases on schedules.

    Besides, the any OS is just as vulnerable as the other. They're simply lines of codes, some better implemented than others. They still can be brought down to its knees.
    Reply
  • cadder
    With the MAC ads on TV and elsewhere thumbing up their noses at viruses, I think it's only a matter of time before virus writers take up the challenge, that is unless virus writers are MAC people themselves.
    Reply
  • SAL-e
    There is no away to idiot-prove any system. If the user don't know what he/she is doing, he/she will be victim of social-engineering attack. For that you don't need to write any viruses. Just ask them for their username and password and they happily will give them to you.
    Even if some one writes a virus for Linux that some how runs automatically or by users action the worst damage would be to the users profile, not the core of the system. You need to spend really great time and effort to misconfigure the Linux in order to have the same level of problems like Windows. I think MS is taking notice of that and the new Windows Server 2008 is much better. Who is going to take on the task to teach the users?!
    Reply
  • Flameout
    There's no such thing as 100% security, even for Linux. It may have something to do with how Linux is coded, but for the most part, it's because Linux runs only on about 1% of the worlds computers. Whenever I install a linux distro on someones pc, I don't say "you'll never get a virus or malware/spyware" I say "the chances of getting a virus or malware/spyware is about 1 in 100"
    Reply
  • scryer_360
    I've heard of these claims before: that Linux systems are just as vulnerable. But I've never seen any evidence of an actual effective form of attack. Of course, you can still do all sorts of network based-attacks, to bring down a connection, but to actually take control over a Linux system? I've never seen it.

    And there are many things in a Linux system that keeps it safe, sometimes by being overly simplistic even. I don't think any OS is bullet-proof: if it can be built, it can be torn down, if torn down, it can be built. Still, I do believe their are varying degrees of difficulty. This is what keeps people strong in the belief of Linux.

    Besides, if Linux were so easy to crack, then I'd imagine we'd here much, much more often about how servers at major companies and institutions are being taken over by crackers.
    Reply