From secure@sunsc.Eng.Sun.COM Thu Jun  5 11:31:52 1997
Date: Wed, 04 Jun 1997 16:44:15 -0400
From: Sun Security Coordination Team <secure@sunsc.Eng.Sun.COM>
To: best-of-security@suburbia.net
Subject: BoS: Sun Security Bulletin #00141
Resent-Date: Thu, 5 Jun 1997 08:15:46 +1000 (EST)
Resent-From: best-of-security@suburbia.net





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        Sun Microsystems, Inc. Security Bulletin
     
Bulletin Number:  #00141
Date:       4 June 1997
Cross-Ref:    
Title:      Vulnerability in getopt(3)

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the Bulletin is not edited and is attributed to Sun Microsystems. Portions 
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proper attribution is included.

Any other use of this information without the express written consent of 
Sun Microsystems is prohibited. Sun Microsystems expressly disclaims all 
liability for any misuse of this information by any third party.
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1.  Bulletins Topics

    Sun announces the release of patches for Solaris 2.5.1, 2.5, and 2.4 
    (SunOS 5.5.1, 5.5, and 5.4) that relate to a vulnerability with the 
    getopt(3) function in the libc library. Any privileged program (setuid 
    or setgid) that uses getopt(3) may exploit the vulnerability to gain root 
    access.
     
    Sun estimates the release of patches for Solaris 2.4_x86 and 2.3 (SunOS 
    5.4_x86 and 5.3) that relate to the same vulnerability will be available 
    within 1 week and 3 weeks respectively of the date of this bulletin. 
    
    Sun strongly recommends that you:
    
    a. install the patches listed in section 5 immediately on every system 
       running SunOS 5.5.1, 5.5.1_x86, 5.5, 5.5_x86, or 5.4
    b. apply the workarounds specified in section 4 immediately on every
system 
       running SunOS 5.4_x86 or 5.3.
    
2.  Who is Affected
  
       Vulnerable:  SunOS versions 5.5.1, 5.5.1_x86, 5.5, 5.5_x86, 
                                       5.4, 5.4_x86, and 5.3.
      
       Not vulnerable:  All other supported versions of SunOS
          
       This vulnerability is fixed in the upcoming release of Solaris.
     
3.  Understanding the Vulnerability

    The getopt(3) function parses options from a program's command list.
    Due to insufficient bounds checking by getopt(3) while processing command 
    line arguments, it is possible to overwrite the internal stack space of 
    programs that use getopt(3). This may allow users to cause programs using 
    getopt(3) to execute arbitrary commands by supplying carefully crafted 
    arguments to these programs. If these programs are setuid or setgid, then 
    these commands may be run with those privileges. 

    Any dynamically or statically linked setuid or setgid program that uses 
    getopt(3) may be vulnerable.
    
4.  Workarounds

4.1 Dynamically linked programs

    The vulnerability can be exploited by using getopt(3) to print error 
    messages when an invalid option is discovered. These messages can be 
    suppressed by setting "opterr" (a global libc variable) to zero by doing 
    the following:

    As root, execute the following command:

      # adb -w /lib/libc.so.1
      
    Type the following:
    
      opterr?W0
      
    The system will respond with:
                          
      opterr:         0x1             =       0x0

    Type Control-D to exit adb.

    Note that this workaround will suppress getopt(3) error messages from 
    all dynamically linked executables.

4.2 Statically linked programs

    The workaround in 4.1 cannot be applied to statically linked setuid or
    setgid programs. Other than /usr/sbin/static/rcp, Sun is not aware of any 
    other statically linked executable that uses getopt(3). The vulnerability
    in the rcp program can be closed by removing the setuid bit with a command
    such as the following:
    
       chmod 555 /usr/sbin/static/rcp
    
    The rcp program is typically run as root during system boot or recovery
    only.

5.  The vulnerability relating to getopt(3) is fixed by the following patches:

  OS version    Patch ID
  ----------    --------
  SunOS 5.5.1    103612-23
  SunOS 5.5.1_x86         103613-23
       SunOS 5.5    103187-25
       SunOS 5.5_x86           103188-25
       SunOS 5.4               101945-49  
  SunOS 5.4_x86           101946-43  (to be released in 1 week)
       SunOS 5.3               101318-87  (to be released in 3 weeks)

6.  Checksum Table

    The checksum table below shows the BSD checksums (SunOS 5.x:
/usr/ucb/sum),
    SVR4 checksums (SunOS 5.x: /usr/bin/sum), and the MD5 digital signatures 
    for the above-mentioned patches that are available from:
     
       ftp://sunsolve1.sun.com/pub/patches/patches.html
       
    These checksums may not apply if you obtain patches from your answer
    centers. 

File Name    BSD         SVR4      MD5
---------------   ---------    ---------    --------------------------------
103612-23.tar.Z   58756 3133   30630 6266   80BFC84479DAED881141250D924C6B1A
103613-23.tar.Z   25868 2829   1295 5657    5AE2770752A17D853029B539EF94B783
103187-25.tar.Z   64511 3195   17448 6389   36120E6EB91C100EB302CE2FEE96739A
103188-25.tar.Z   07195 2880   23176 5760   6707EAB1BD10B845F535E131836F8DC5
101945-49.tar.Z   25995 10899  19660 21798  D67A5744C87BAD1A31D87AED6DC3C362

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Sun acknowledges with thanks AUSCERT, CERT/CC, and DFNCERT for their
assistance 
in the preparation of this bulletin.

Sun, AUSCERT, CERT/CC, and DFNCERT are members of FIRST, the Forum of
Incident 
Response and Security Teams. For more information about FIRST, visit the
FIRST 
web site at "http://www.first.org/".
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APPENDICES

A.  Patches listed in this bulletin are available to all Sun customers via 
    World Wide Web at:
    
      ftp://sunsolve1.sun.com/pub/patches/patches.html
      
    Customers with Sun support contracts can also obtain patches from local 
    Sun answer centers and SunSITEs worldwide.
    
B.  To report or inquire about a security problem with Sun software, contact 
    one or more of the following:
  
        - Your local Sun answer centers
        - Your representative computer security response team, such as CERT 
        - Sun Security Coordination Team. Send email to:
   
         security-alert@sun.com
         
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