Re: Samba 3.x + kernel 2.6.x local root vulnerability

From: Seth Arnold (sarnold_at_wirex.com)
Date: 02/09/04

  • Next message: Larry Seltzer: "RE: Outbreak warning: possibly Mydoom.C (Now Deadhat/Vesser)"
    Date: Mon, 9 Feb 2004 14:03:47 -0800
    To: bugtraq@securityfocus.com
    
    
    

    On Mon, Feb 09, 2004 at 10:23:03PM +0100, Michal Medvecky wrote:
    > Confirmed to work on all 2.6.x kernels, not confirmed on 2.4.x.

    I haven't got a clue what you're trying to accomplish. If you don't want
    a setuid execute, DON'T RUN chmod +s! You don't even need samba to
    accomplish this:

    $ cat > a.c <<EOF
    > main()
    > {
    > setuid(0);
    > setgid(0);
    > system("/bin/bash");
    > }
    > EOF
    $ make a
    cc a.c -o a
    $ sudo chown root:root a
    Password:
    $ sudo chmod +s a
    $ ./a
    $ id
    uid=0(root) gid=0(root) groups=500(sarnold)
    $ exit

    I expect this behaviour out of every Linux, BSD, commercial Unix,
    Windows NT with POSIX emulation, QNX, etc. (For the curious, this was
    run on Linux 2.4.21-9.EL_imnx_2smp.)

    Can you please explain what specifically bothers you?

    Thanks :)

    -- 
    Immunix Secured Linux Distribution: http://immunix.org/
    
    


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