AUSCERT External Security Bulletin Redistribution

                  ESB-2003.0570 -- SGI Security Advisory
            Denial of Service Vulnerability in NFS XDR decoding
                              15 August 2003


        AusCERT Security Bulletin Summary

Product:                nfsd
Publisher:              SGI
Operating System:       IRIX prior to 6.5.20
Platform:               MIPS
Impact:                 Denial of Service
Access Required:        Remote
CVE Names:              CAN-2003-0576

- --------------------------BEGIN INCLUDED TEXT--------------------


                           SGI Security Advisory

  Title    : Denial of Service Vulnerability in NFS XDR decoding
  Number   : 20030801-01-P
  Date     : August 13, 2003
  Reference: CVE 2003-0576
  Reference: SGI BUG 894659
  Fixed in : IRIX 6.5.20 or patches 5229, 5230, 5240, 5241, 5227, 5228

SGI provides this information freely to the SGI user community for its
consideration, interpretation, implementation and use.  SGI recommends that
this information be acted upon as soon as possible.

SGI provides the information in this Security Advisory on an "AS-IS" basis
only, and disclaims all warranties with respect thereto, express, implied
or otherwise, including, without limitation, any warranty of merchantability
or fitness for a particular purpose.  In no event shall SGI be liable for
any loss of profits, loss of business, loss of data or for any indirect,
special, exemplary, incidental or consequential damages of any kind arising
from your use of, failure to use or improper use of any of the instructions
or information in this Security Advisory.

- - -----------------------
- - --- Issue Specifics ---
- - -----------------------

It's been reported that it is possible to create a Denial of Service attack
on the IRIX nfsd through the use of carefully crafted packets which cause
XDR decoding errors. This can lead to kernel panicing the system.  No local account or access to an NFS mount point is required, so this could be constructed as a remote exploit.

SGI has investigated the issue and recommends the following steps for
neutralizing the exposure.  It is HIGHLY RECOMMENDED that these measures be
implemented on ALL vulnerable SGI systems.

These issues have been corrected with patches and in future releases of IRIX.

- - --------------
- - --- Impact ---
- - --------------

nfs is installed by default on IRIX 6.5 systems.

To determine the version of IRIX you are running, execute the following

  # /bin/uname -R

That will return a result similar to the following:

  # 6.5 6.5.19f

The first number ("6.5") is the release name, the second ("6.5.16f" in this
case) is the extended release name.  The extended release name is the
"version" we refer to throughout this document.

To see if nfs is installed, execute the following command:

$ versions -b | grep nfs
I  nfs                  05/15/2003  Network File System, 6.5.20f

- - ----------------------------
- - --- Temporary Workaround ---
- - ----------------------------

There is no effective workaround available for these problems.  SGI
recommends either upgrading to IRIX 6.5.20, or installing the appropriate
patch from the listing below.

- - ----------------
- - --- Solution ---
- - ----------------

SGI has provided a series of patches for these vulnerabilities. Our
recommendation is to upgrade to IRIX 6.5.20, or install the appropriate

   OS Version     Vulnerable?     Patch #      Other Actions
   ----------     -----------     -------      -------------
   IRIX 3.x        unknown                     Note 1
   IRIX 4.x        unknown                     Note 1
   IRIX 5.x        unknown                     Note 1
   IRIX 6.0.x      unknown                     Note 1
   IRIX 6.1        unknown                     Note 1
   IRIX 6.2        unknown                     Note 1
   IRIX 6.3        unknown                     Note 1
   IRIX 6.4        unknown                     Note 1
   IRIX 6.5          yes                       Notes 2 & 3
   IRIX 6.5.1        yes                       Notes 2 & 3
   IRIX 6.5.2        yes                       Notes 2 & 3
   IRIX 6.5.3        yes                       Notes 2 & 3
   IRIX 6.5.4        yes                       Notes 2 & 3
   IRIX 6.5.5        yes                       Notes 2 & 3
   IRIX 6.5.6        yes                       Notes 2 & 3
   IRIX 6.5.7        yes                       Notes 2 & 3
   IRIX 6.5.8        yes                       Notes 2 & 3
   IRIX 6.5.9        yes                       Notes 2 & 3
   IRIX 6.5.10       yes                       Notes 2 & 3
   IRIX 6.5.11       yes                       Notes 2 & 3
   IRIX 6.5.12       yes                       Notes 2 & 3
   IRIX 6.5.13       yes                       Notes 2 & 3
   IRIX 6.5.14       yes                       Notes 2 & 3
   IRIX 6.5.15       yes                       Notes 2 & 3
   IRIX 6.5.16       yes                       Notes 2 & 3
   IRIX 6.5.17m      yes          5229         Notes 2, 4 & 5
   IRIX 6.5.17f      yes          5230         Notes 2, 4 & 5
   IRIX 6.5.18m      yes          5240         Notes 2, 4 & 5
   IRIX 6.5.18f      yes          5241         Notes 2, 4 & 5
   IRIX 6.5.19m      yes          5227         Notes 2, 4 & 5
   IRIX 6.5.19f      yes          5228         Notes 2, 4 & 5
   IRIX 6.5.20        no
   IRIX 6.5.21        no


     1) This version of the IRIX operating has been retired. Upgrade to an
        actively supported IRIX operating system.  See
        http://support.sgi.com for more information.

     2) If you have not received an IRIX 6.5.X CD for IRIX 6.5, contact your
        SGI Support Provider or URL: http://support.sgi.com

     3) Upgrade to IRIX 6.5.20.

     4) Upgrade to IRIX 6.5.20 or install the patch.

     5) Note that these patches also include other fixes that are not
        security related.

             ##### Patch File Checksums ####
Filename:                 README.patch.5227
Algorithm #1 (sum -r):    12931 11 README.patch.5227
Algorithm #2 (sum):       22414 11 README.patch.5227
MD5 checksum:             7ED03B2BE0DC6DE5D33D81339AB14017

Filename:                 patchSG0005227
Algorithm #1 (sum -r):    11461 5 patchSG0005227
Algorithm #2 (sum):       37091 5 patchSG0005227
MD5 checksum:             6159ACA5DADB447DBAC03E2713B397F9

Filename:                 patchSG0005227.eoe_sw
Algorithm #1 (sum -r):    09551 8277 patchSG0005227.eoe_sw
Algorithm #2 (sum):       30759 8277 patchSG0005227.eoe_sw
MD5 checksum:             E5339A8B3C9231CC8EFD58CB59FEED1C

Filename:                 patchSG0005227.idb
Algorithm #1 (sum -r):    20594 41 patchSG0005227.idb
Algorithm #2 (sum):       1408 41 patchSG0005227.idb
MD5 checksum:             32BF7447A53E8A9DAD84A2B416674F16

Filename:                 patchSG0005227.irix_dev_sw
Algorithm #1 (sum -r):    38535 10 patchSG0005227.irix_dev_sw
Algorithm #2 (sum):       12894 10 patchSG0005227.irix_dev_sw
MD5 checksum:             D53D8B75C2D7B3A3C925ADCFB35F8B95

Filename:                 patchSG0005227.nfs_sw
Algorithm #1 (sum -r):    31365 5170 patchSG0005227.nfs_sw
Algorithm #2 (sum):       49085 5170 patchSG0005227.nfs_sw
MD5 checksum:             E4F9D5896C4272B81430CF0C8611487C

Filename:                 README.patch.5228
Algorithm #1 (sum -r):    16002 11 README.patch.5228
Algorithm #2 (sum):       22374 11 README.patch.5228
MD5 checksum:             9ED598FCE24B45D9B821BBED49EF4401

Filename:                 patchSG0005228
Algorithm #1 (sum -r):    37726 5 patchSG0005228
Algorithm #2 (sum):       23213 5 patchSG0005228
MD5 checksum:             3167AD1850E8F6C2CA50F1679C402315

Filename:                 patchSG0005228.eoe_sw
Algorithm #1 (sum -r):    16223 8422 patchSG0005228.eoe_sw
Algorithm #2 (sum):       46670 8422 patchSG0005228.eoe_sw
MD5 checksum:             EFB7678E25D935BFDF9B8531786FE67A

Filename:                 patchSG0005228.idb
Algorithm #1 (sum -r):    53530 41 patchSG0005228.idb
Algorithm #2 (sum):       21988 41 patchSG0005228.idb
MD5 checksum:             92B4E031662EEF88415D18A2ABE8CA74

Filename:                 patchSG0005228.irix_dev_sw
Algorithm #1 (sum -r):    38535 10 patchSG0005228.irix_dev_sw
Algorithm #2 (sum):       12894 10 patchSG0005228.irix_dev_sw
MD5 checksum:             D53D8B75C2D7B3A3C925ADCFB35F8B95

Filename:                 patchSG0005228.nfs_sw
Algorithm #1 (sum -r):    17463 5280 patchSG0005228.nfs_sw
Algorithm #2 (sum):       25872 5280 patchSG0005228.nfs_sw
MD5 checksum:             DCEAE822C6F2AE0335987F8D4CB22037

Filename:                 README.patch.5229
Algorithm #1 (sum -r):    01277 9 README.patch.5229
Algorithm #2 (sum):       828 9 README.patch.5229
MD5 checksum:             27F5BC248785EB885A13CC882BC3546F

Filename:                 patchSG0005229
Algorithm #1 (sum -r):    35802 2 patchSG0005229
Algorithm #2 (sum):       57891 2 patchSG0005229
MD5 checksum:             FC923269FA4B82B7B74C6406982A9BF7

Filename:                 patchSG0005229.eoe_sw
Algorithm #1 (sum -r):    64586 5941 patchSG0005229.eoe_sw
Algorithm #2 (sum):       16069 5941 patchSG0005229.eoe_sw
MD5 checksum:             566A389D3F36A1398FA7EEC56BF175B9

Filename:                 patchSG0005229.idb
Algorithm #1 (sum -r):    38401 26 patchSG0005229.idb
Algorithm #2 (sum):       7466 26 patchSG0005229.idb
MD5 checksum:             60B99ECECF97909AEF3F4A2DE88D82F5

Filename:                 patchSG0005229.irix_dev_sw
Algorithm #1 (sum -r):    34148 1 patchSG0005229.irix_dev_sw
Algorithm #2 (sum):       774 1 patchSG0005229.irix_dev_sw
MD5 checksum:             782988FA4FAC22A5F522D4985B47D6CB

Filename:                 patchSG0005229.nfs_sw
Algorithm #1 (sum -r):    09009 4240 patchSG0005229.nfs_sw
Algorithm #2 (sum):       65046 4240 patchSG0005229.nfs_sw
MD5 checksum:             C8D28197ABBFB214E312BE5474089CFE

Filename:                 README.patch.5230
Algorithm #1 (sum -r):    12236 9 README.patch.5230
Algorithm #2 (sum):       63420 9 README.patch.5230
MD5 checksum:             12E5B2318D3B3516409D084C27387163

Filename:                 patchSG0005230
Algorithm #1 (sum -r):    50666 2 patchSG0005230
Algorithm #2 (sum):       59311 2 patchSG0005230
MD5 checksum:             44FE30C482E00898A48FB5C865A63FF3

Filename:                 patchSG0005230.eoe_sw
Algorithm #1 (sum -r):    29102 6011 patchSG0005230.eoe_sw
Algorithm #2 (sum):       39184 6011 patchSG0005230.eoe_sw
MD5 checksum:             3BEB537E47F3A199311CD8D0B1819D04

Filename:                 patchSG0005230.idb
Algorithm #1 (sum -r):    05200 26 patchSG0005230.idb
Algorithm #2 (sum):       7102 26 patchSG0005230.idb
MD5 checksum:             3E3AE7ACC124D1789D16E6510C58D9DB

Filename:                 patchSG0005230.nfs_sw
Algorithm #1 (sum -r):    47262 4333 patchSG0005230.nfs_sw
Algorithm #2 (sum):       29161 4333 patchSG0005230.nfs_sw
MD5 checksum:             08121F4C697F3FF84C3555B05403ECCD

Filename:                 README.patch.5240
Algorithm #1 (sum -r):    49573 10 README.patch.5240
Algorithm #2 (sum):       6006 10 README.patch.5240
MD5 checksum:             35487EA3FE038B6460A592261C04EFCD

Filename:                 patchSG0005240
Algorithm #1 (sum -r):    07297 4 patchSG0005240
Algorithm #2 (sum):       50257 4 patchSG0005240
MD5 checksum:             256FFFFC0DD9FD4FB7AABC2016E77E76

Filename:                 patchSG0005240.eoe_sw
Algorithm #1 (sum -r):    47611 7496 patchSG0005240.eoe_sw
Algorithm #2 (sum):       33432 7496 patchSG0005240.eoe_sw
MD5 checksum:             694361E17A3C8147099E946EBD277A08

Filename:                 patchSG0005240.idb
Algorithm #1 (sum -r):    06906 26 patchSG0005240.idb
Algorithm #2 (sum):       63464 26 patchSG0005240.idb
MD5 checksum:             5B8066AEB25AE8DC988181B6318FA0FD

Filename:                 patchSG0005240.irix_dev_sw
Algorithm #1 (sum -r):    38535 10 patchSG0005240.irix_dev_sw
Algorithm #2 (sum):       12894 10 patchSG0005240.irix_dev_sw
MD5 checksum:             D53D8B75C2D7B3A3C925ADCFB35F8B95

Filename:                 patchSG0005240.nfs_sw
Algorithm #1 (sum -r):    40380 3891 patchSG0005240.nfs_sw
Algorithm #2 (sum):       34675 3891 patchSG0005240.nfs_sw
MD5 checksum:             71E454F5DF8B7B231BE5534CEFFC1EC8

Filename:                 README.patch.5241
Algorithm #1 (sum -r):    12584 10 README.patch.5241
Algorithm #2 (sum):       5979 10 README.patch.5241
MD5 checksum:             4C1EE3B73CDD4851D06E73BBB21D65D1

Filename:                 patchSG0005241
Algorithm #1 (sum -r):    05691 5 patchSG0005241
Algorithm #2 (sum):       13971 5 patchSG0005241
MD5 checksum:             5C6423A1D130E749E6644CDE3CD73FF3

Filename:                 patchSG0005241.eoe_sw
Algorithm #1 (sum -r):    00113 7607 patchSG0005241.eoe_sw
Algorithm #2 (sum):       34258 7607 patchSG0005241.eoe_sw
MD5 checksum:             5596F7572B50139B776BF011C70E82FC

Filename:                 patchSG0005241.idb
Algorithm #1 (sum -r):    22072 26 patchSG0005241.idb
Algorithm #2 (sum):       63480 26 patchSG0005241.idb
MD5 checksum:             3CC8B8E45D008D213B8CB84034675509

Filename:                 patchSG0005241.irix_dev_sw
Algorithm #1 (sum -r):    38535 10 patchSG0005241.irix_dev_sw
Algorithm #2 (sum):       12894 10 patchSG0005241.irix_dev_sw
MD5 checksum:             D53D8B75C2D7B3A3C925ADCFB35F8B95

Filename:                 patchSG0005241.nfs_sw
Algorithm #1 (sum -r):    09049 3954 patchSG0005241.nfs_sw
Algorithm #2 (sum):       32772 3954 patchSG0005241.nfs_sw
MD5 checksum:             B28A5B503F0B5C85D62C76A666667685

- - -------------
- - --- Links ---
- - -------------

SGI Security Advisories can be found at:
http://www.sgi.com/support/security/ and

SGI Security Patches can be found at:
http://www.sgi.com/support/security/ and

SGI patches for IRIX can be found at the following patch servers:
http://support.sgi.com/ and ftp://patches.sgi.com/

SGI freeware updates for IRIX can be found at:

SGI patches and RPMs for Linux can be found at:

SGI patches for Windows NT or 2000 can be found at:

IRIX 5.2-6.4 Recommended/Required Patch Sets can be found at:
http://support.sgi.com/ and ftp://patches.sgi.com/support/patchset/

IRIX 6.5 Maintenance Release Streams can be found at:

IRIX 6.5 Software Update CDs can be obtained from:

The primary SGI anonymous FTP site for security advisories and patches is
patches.sgi.com.  Security advisories and patches are located under the URL

For security and patch management reasons, ftp.sgi.com (mirrors
patches.sgi.com security FTP repository) lags behind and does not do a
real-time update.

- - -----------------------------------------
- - --- SGI Security Information/Contacts ---
- - -----------------------------------------

If there are questions about this document, email can be sent to


SGI provides security information and patches for use by the entire SGI
community.  This information is freely available to any person needing the
information and is available via anonymous FTP and the Web.

The primary SGI anonymous FTP site for security advisories and patches is
patches.sgi.com.  Security advisories and patches are located under the URL

The SGI Security Headquarters Web page is accessible at the URL:

For issues with the patches on the FTP sites, email can be sent to

For assistance obtaining or working with security patches, please
contact your SGI support provider.


SGI provides a free security mailing list service called wiretap and
encourages interested parties to self-subscribe to receive (via email) all
SGI Security Advisories when they are released. Subscribing to the mailing
list can be done via the Web
(http://www.sgi.com/support/security/wiretap.html) or by sending email to
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% mail wiretap-request@sgi.com
subscribe wiretap <YourEmailAddress such as midwatch@sgi.com >

In the example above, <YourEmailAddress> is the email address that you wish
the mailing list information sent to.  The word end must be on a separate
line to indicate the end of the body of the message. The control-d (^d) is
used to indicate to the mail program that you are finished composing the
mail message.


SGI provides a comprehensive customer World Wide Web site. This site is
located at http://www.sgi.com/support/security/ .


If there are general security questions on SGI systems, email can be sent to

For reporting *NEW* SGI security issues, email can be sent to
security-alert@sgi.com or contact your SGI support provider.  A support
contract is not required for submitting a security report.

      This information is provided freely to all interested parties
      and may be redistributed provided that it is not altered in any
      way, SGI is appropriately credited and the document retains and
      includes its valid PGP signature.

Version: 2.6.2


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