L-028: Solaris ARP Setgid Vulnerability

PROBLEM:      Address Resolution Protocol (ARP) command uses Set group ID
              (Setgid), and is therefore susceptible to certain setgid attacks.
PLATFORM:     All versions prior to Solaris 8. (includes: Solaris 7, 7_x86,
              2.6, 2_x86, etc).
DAMAGE:       Exploiting setgid could result in overflow of stack, and possible
              root compromise.
SOLUTION:     Apply patches. Patch IDs are provided.

VULNERABILITY  HIGH. Rated high because of the potential of root compromise.
ASSESSMENT:


 ********* Begin Sun Microsystems Advisory ********** 

________________________________________________________________________________
          Sun Microsystems, Inc. Security Bulletin

Bulletin Number:      #00200
Date:                 January 12, 2001
Cross-Ref:            Bugtraq ID 2193
Title:                arp
________________________________________________________________________________

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________________________________________________________________________________
1.  Bulletins Topics

    Sun announces the release of patches for Solaris(tm) 7, 2.6, 2.5.1,
    2.5, and 2.4 (SunOS(tm) 5.7, 5.6, 5.5.1, 5.5, and 5.4) which relate
    to a setgid vulnerability in arp.

2.  Who is Affected

    Versions of arp in Solaris prior to Solaris 8

       Vulnerable:         Solaris 7, 7_x86, 2.6, 2.6_x86, 2.5.1,
                               2.5.1_x86, 2.5, 2.5_x86, 2.4, 2.4_x86

       Not vulnerable:     Solaris 8.

3.  Understanding the Vulnerability

    The arp program displays and modifies the Internet-to-Ethernet address
    translation tables used by the address resolution protocol (arp).  Prior
    to Solaris 8, arp was setgid making it susceptible to certain setgid
    attacks.

    A malicious user could overflow the stack and execute shellcode which
    could allow unauthorized root access.

4.  List of Patches

    The following patches are available in relation to the above problem.

    OS Version          Patch ID
    __________          _________
    SunOS 5.7           109709-01
    SunOS 5.7_x86       109710-01
    SunOS 5.6           109719-01
    SunOS 5.6_x86       109720-01
    SunOS 5.5.1         109721-01
    SunOS 5.5.1_x86     109722-01
    SunOS 5.5           109707-01
    SunOS 5.5_x86       109708-01
    SunOS 5.4           109723-01
    SunOS 5.4_x86       109724-01
______________________________________________________________________________
Sun acknowledges, with thanks, Dave Ahmed of Security-Focus.com and Pablo Sor
from the AFIP Computer Security Department for their assistance with this
matter.
http://www.securityfocus.com/bid/2193
________________________________________________________________________________

APPENDICES

A.   Patches listed in this bulletin are available to all Sun customers at:

     http://sunsolve.sun.com/securitypatch

B.   Checksums for the patches listed in this bulletin are available at:

     ftp://sunsolve.sun.com/pub/patches/CHECKSUMS

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E.  To report or inquire about a security problem with Sun software, contact
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