Re: cron exploit?

From: Matt Zimmerman (mdz_at_debian.org)
Date: 09/29/03

  • Next message: Harlan Carvey: "Re: Repository of virus/worm propagation methods?"
    Date: Mon, 29 Sep 2003 13:30:24 -0400
    To: Incidents <incidents@securityfocus.com>
    
    

    On Sun, Sep 28, 2003 at 03:09:01PM -0700, Jeremy Hanmer wrote:

    > We just had a Debian (Woody) box get rooted, apparently by a cron
    > exploit mentioned here: http://www.codon.org.uk/~mjg59/kern/jmb73bash
    >
    > We've contacted the package maintainer, but has anybody else seen
    > anything like this floating around yet? It's pretty worrisome since we
    > have a couple hundred linux boxes that must run cron for various
    > reasons.

    As I said before, there is no evidence here of a cron exploit, and it raises
    unnecessary alarm to claim that there is one. It looks like you had a
    world-writable script (or a script owned by the unprivileged user who was
    exploited) in /etc/cron.daily, and so the intruder modified that script in
    order to execute commands as root.

    All signs point to a local configuration error.

    > echo chown root:root /tmp/rmsd >> mkwebuserlist
    > echo chmod 4755 /tmp/rmsd >> mkwebuserlist

    -- 
     - mdz
    ---------------------------------------------------------------------------
    ----------------------------------------------------------------------------
    

  • Next message: Harlan Carvey: "Re: Repository of virus/worm propagation methods?"

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