[Full-Disclosure] 3COM 3crwe754g72-a Administration interface code injection (DHCP)

From: Cyrille Barthelemy (cb-publicbox_at_ifrance.com)
Date: 10/18/04

  • Next message: Todd Towles: "RE: [Full-Disclosure] Full-Disclosure Posts"
    To: full-disclosure@lists.netsys.com
    Date: Mon, 18 Oct 2004 14:17:48 +0200
    
    

    Title: 3COM 3crwe754g72-a Administration interface code injection
    Class: Design error
    Affects:
     3com 3crwe754g72-a
          v 1.11
          v 1.13
          v 1.24
    Id: cbsa-0001
    Release Date: 2004-10-18
    Author : Cyrille Barthelemy <cb-publicbox@ifrance.com>

    -- 1. Introduction
    ------------------
    3Com 3crwe754g72-a is a bundle product which provides misc services
    (adsl modem, 802.11b/g access point, router, dhcp server, snmp agent ...).
    All services are manageable using a web interface.

    As reported in a previous advisory this product suffer from various
    vulnerability. The way DHCP REQUEST are handled allow an attacker to inject
    code into the administration interface.

    -- 2. Problem
    -------------
    The web interface used to administrate the router display a list of the DHCP
    client with the following informations :
           - ip address allocated
           - hostname
           - MAC address
    The second information can be submitted by a client using DHCP options, and no
    content filtering will be done by the dhcp daemon or the web interface.

    -- 3. Exploitation
    ------------------
    The exploitation can be made using the DHCPing program with the following
    invocation:

    root# dhcping -opttype 'REQUEST' -opthostname '<h1>Oops</h1>' -z

    The injection seems is limited to 20 characters, but this limitation can be
    bypassed using the same technique descrubed by Gregory Duchemin (see
    References)

    -- 4. Solution
    --------------
    Apply the firmware upgrade available at 3com support site :
    http://www.3com.com/products/en_US/result.jsp?selected=6&sort=effdt&sku=3CRWE754G72-A&order=desc

    -- 5. References
    ----------------
       - 3com website
         http://www.3com.com

       - DHCPing web site
         http://dhcping.openwall.net

       - DLINK 614+, script injection vulnerability
         http://securityfocus.com/archive/1/366615/2004-06-21/2004-06-27/0

    -- 10. History
    --------------
    2004-07-02.
     - Vulnerability discovered
    2004-08-24
     - 3com contacted at security@3com.com
    2004-09-08
     - vendor response
    2004-10-14
     - patch available

    -- 11. Contact information
    ------------------------
    Cyrille Barthelemy <cb-publicbox@ifrance.com>
    Web Site : http://www.cyrille-barthelemy.com

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  • Next message: Todd Towles: "RE: [Full-Disclosure] Full-Disclosure Posts"

    Relevant Pages

    • Re: Configuring dhcp on cisco 3750
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    • Re: Conflicting uses of "ip dhcp-server" -- design flaw?
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    • Re: Configuring dhcp on cisco 3750
      ... for dhcp requests and the proceeding dhcp traffic. ... I connected one of the clients to the dhcp server back-2-back to ... interface GigabitEthernet1/0/1 ...
      (comp.dcom.sys.cisco)
    • Re: Configuring dhcp on cisco 3750
      ... for dhcp requests and the proceeding dhcp traffic. ... interface GigabitEthernet1/0/1 ... switchport access vlan 2 ...
      (comp.dcom.sys.cisco)