rpc.pcnfsd vulnerabilities on IRIX

Type securityvulns
Reporter Securityvulns
Modified 2002-08-03T00:00:00



                      SGI Security Advisory

    Title:      rpc.pcnfsd vulnerabilities
    Number:     20020802-01-I
    Date:       August 1, 2002
    Reference:  CERT® Advisory CA-1996-08
    Reference:  CAN-1999-0078

  • --- Issue Specifics ---

It's been reported that there are vulnerabilities in the rpc.pcnfsd daemon that is supplied with IRIX 6.5.

See http://www.cert.org/advisories/CA-1996-08.html for additional details.

These vulnerabilities were assigned the following CVE: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-1999-0078

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.

  • --- Impact ---

The pcnfsd binary is not installed by default on IRIX 6.5 systems. It is part of the optional pcnfsd subsystem on the NFS CD.

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

# uname -R

That will return a result similar to the following:

# 6.5 6.5.16f

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 pcnfs is installed, execute the following command:

# versions pcnfsd

I pcnfsd 02/24/1999 PC-NFS 2.0.2 Server Components I pcnfsd.man 02/24/1999 PC-NFS Server Component Documentation I pcnfsd.man.manpages 02/24/1999 PC-NFS Server Man Pages I pcnfsd.man.relnotes 02/24/1999 PC-NFS Server Release Notes I pcnfsd.spool 02/24/1999 PC-NFS Server Component Print Spooling I pcnfsd.spool.directory 02/24/1999 PC-NFS Server Print Spooling Directory I pcnfsd.sw 02/24/1999 PC-NFS Server Component Software I pcnfsd.sw.base 02/24/1999 PC-NFS Server Base Subsystem

If the result is similar to that shown above, then pcnfs is installed and the system may be vulnerable.

  • --- Temporary Workaround ---

SGI has moved the pcnfs product to "Courtesy" mode, and there will be no fixes released for this problem. See the following URL for details on the different support modes:


SGI recommends uninstalling the pcnfsd package from the system, by following these steps:

$ su - # versions remove pcnfsd

It is not necessary to reboot the system after doing this, but you should unexport and remove the /var/spool/pcnfs line in /etc/exports and remove the /var/spool/pcnfs directory:

# exportfs -u /var/spool/pcnfs # rmdir /var/spool/pcnfs # cp /etc/exports /etc/exports.OLD # sed '\/var\/spool\/pcnfs/d' /etc/exports > /tmp/tmpfile; mv /tmp/tmpfile /etc/exports

  • --- Solution ---

SGI has not provided patches for this vulnerability. Our recommendation is to uninstall the product as outlined above.

The pcnfs package is no longer supported, but as a courtesy to SGI customers a newer revision (pcnfsd-93.02.16-cert) has been ported by the SGI Freeware volunteers and is available at http://freeware.sgi.com/index-by-alpha.html. Please note that as with all SGI Freeware, this package is not supported by SGI.

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


 1) This version of the IRIX operating has been retired. Upgrade to an
    actively supported IRIX operating system.  See
    http://support.sgi.com/irix/news/index.html#policy for more

 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/irix/swupdates/

 3) Uninstall the pcnfsd package as described above.

  • --- Acknowledgments ----

SGI wishes to thank Avalon Security Research, Rob Thomas, CERT, FIRST and the users of the Internet Community at large for their assistance in this matter.

  • --- Links ---

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

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

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

SGI freeware updates for IRIX can be found at: http://freeware.sgi.com/

SGI fixes for SGI open sourced code can be found on: http://oss.sgi.com/projects/

SGI patches and RPMs for Linux can be found at: http://support.sgi.com/linux/ or http://oss.sgi.com/projects/sgilinux-combined/download/security-fixes/

SGI patches for Windows NT or 2000 can be found at: http://support.sgi.com/nt/

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

IRIX 6.5 Maintenance Release Streams can be found at: http://support.sgi.com/colls/patches/tools/relstream/index.html

IRIX 6.5 Software Update CDs can be obtained from: http://support.sgi.com/irix/swupdates/

The primary SGI anonymous FTP site for security advisories and patches is patches.sgi.com ( Security advisories and patches are located under the URL ftp://patches.sgi.com/support/free/security/

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 security-info@sgi.com.


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The primary SGI anonymous FTP site for security advisories and patches is patches.sgi.com ( Security advisories and patches are located under the URL ftp://patches.sgi.com/support/free/security/

The SGI Security Headquarters Web page is accessible at the URL: http://www.sgi.com/support/security/

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