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This is a really dumb article.

The fork() command is NOT an exploit. It's just a unix system call that anyone who has done any unix system programming knows about.

To say that this is a linux security flaw is as ridiculous as claiming that the "del" command in Windows's dos box is a security flaw. Anyone can bring down a Windows machine by typing something like "del \windows\*.exe" or something like that. Does this mean Windows has a serious security flaw? Of course not.

And what makes it even more absurd is the fact that the fork system call exists in Windows too! (because Windows is posix-compliant). So everything claimed in this article about linux applies to Windows.

Anyways, any sysadmin worth a dime knows not to allow non-privileged users to run fork() in an infinite loop or anything similar.

The thing is, on a default Windows install (I think -- been a while), a user can't del C:\windows because he doesn't have permission. Any user on Linux, however, can type :(){ :&:;};: into the terminal and bomb his machine. (Imagine BillG or Steve Ballmer doing this at the Longhorn release gala to demonstrate the superiority of their OS.) The admin will come down on him with the wrath of God, but he can do it. If Osama gets a shell account on a CIA computer, but doesn't have read or write access to any files, and can't get out of a chroot jail, he can still bomb it.

I assume he can also do it on Windows, but it would probably take a bit more work than typing one line at a command prompt. Either a crazy batch file or a binary.

The issue, I think, is that most Linux distributions don't have sane ulimits set, or don't have an easy way for them to be set during the install process. Given the message traffic on the Redhat list and Linux websites -- consisting mostly of, "It's the admin's fault, man ulimit, hurr hurr hurr," -- this won't be fixed, or if it is, very quietly.

How to tell if your son is a computer hacker:

Is your son obsessed with "Lunix"?

BSD, Lunix, Debian and Mandrake are all versions of an illegal hacker operation system, invented by a Soviet computer hacker named Linyos Torovoltos, before the Russians lost the Cold War. It is based on a program called "xenix", which was written by Microsoft for the US government. These programs are used by hackers to break into other people's computer systems to steal credit card numbers. They may also be used to break into people's stereos to steal their music, using the "mp3" program. Torovoltos is a notorious hacker, responsible for writing many hacker programs, such as "telnet", which is used by hackers to connect to machines on the internet without using a telephone.

Your son may try to install "lunix" on your hard drive. If he is careful, you may not notice its presence, however, lunix is a capricious beast, and if handled incorrectly, your son may damage your computer, and even break it completely by deleting Windows, at which point you will have to have your computer repaired by a professional.

If you see the word "LILO" during your windows startup (just after you turn the machine on), your son has installed lunix. In order to get rid of it, you will have to send your computer back to the manufacturer, and have them fit a new hard drive. Lunix is extremely dangerous software, and cannot be removed without destroying part of your hard disk surface.

Has your child asked for new hardware?

Computer hackers are often limited by conventional computer hardware. They may request "faster" video cards, and larger hard drives, or even more memory. If your son starts requesting these devices, it is possible that he has a legitimate need. You can best ensure that you are buying legal, trustworthy hardware by only buying replacement parts from your computer's manufacturer.

If your son has requested a new "processor" from a company called "AMD", this is genuine cause for alarm. AMD is a third-world based company who make inferior, "knock-off" copies of American processor chips. They use child labor extensively in their third world sweatshops, and they deliberately disable the security features that American processor makers, such as Intel, use to prevent hacking. AMD chips are never sold in stores, and you will most likely be told that you have to order them from internet sites. Do not buy this chip! This is one request that you must refuse your son, if you are to have any hope of raising him well.

Are you finding programs on your computer that you don't remember installing?

Your son will probably try to install some hacker software. He may attempt to conceal the presence of the software in some way, but you can usually find any new programs by reading through the programs listed under "Install/Remove Programs" in your control panel. Popular hacker software includes "Comet Cursor", "Bonzi Buddy" and "Flash".

The best option is to confront your son with the evidence, and force him to remove the offending programs. He will probably try to install the software again, but you will be able to tell that this is happening, if your machine offers to "download" one of the hacker applications. If this happens, it is time to give your son a stern talking to, and possibly consider punishing him with a grounding.

The fork() command is NOT an exploit. It's just a unix system call that anyone who has done any unix system programming knows about.

Wrong. It's a denial of service attack. It requires no special privileges to do a fork. That's the dangerous part about it.

And what makes it even more absurd is the fact that the fork system call exists in Windows too! (because Windows is posix-compliant). So everything claimed in this article about linux applies to Windows.

Nobody's claiming otherwise. Do you see evidence to the contrary?

Anyways, any sysadmin worth a dime knows not to allow non-privileged users to run fork() in an infinite loop or anything similar.

Oh, really. What's the command to "not allow non-privileged users to run fork() in an infinite loop"? I'm curious to know -- and I'm sure that sysadmins would like to know. BWHAHAHAHAHAHAHAHA! Let's not kid ourselves -- there is no such command. The only way to handle this condition currently (without some kind of additional kernel security) is to notice that a particular user is creating a lot of processes and kill them (or the user). Do you have a script that counts the number of user processes and starts killing them if the user exceeds some magic threshold? In all likelihood, no, you don't.