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Date:         Mon, 14 Aug 2000 16:56:31 -0700
From: SGI Security Coordinator <agent99@CSD.SGI.COM>
Subject:      Linux Kernel Capability Vulnerability
To: BUGTRAQ@SECURITYFOCUS.COM

-----BEGIN PGP SIGNED MESSAGE-----

______________________________________________________________________________
                          SGI Security Advisory

        Title:   Linux Kernel Capability Vulnerability
        Number:  20000802-01-P
        Date:    August 14, 2000
______________________________________________________________________________

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 ---
- -----------------------

Sendmail, Inc. (http://www.sendmail.com/) reported a vulnerability in the
capability model of the Linux kernel which can lead to a root compromise.

SGI ProPack for Linux uses a modified kernel optimized for SGI Linux
hardware.  This kernel is based on the standard kernel available from
http://www.kernel.org/ with SGI patches from http://oss.sgi.com/

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.  This issue will be
corrected in future releases of SGI ProPack for Linux.


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

SGI ProPack for Linux comes with a modified Linux kernel and is installed
by default on various Linux distributions.  For more information, see:
http://oss.sgi.com/projects/ or http://support.sgi.com/linux/

A local user account on the vulnerable system is required in order to
exploit capability model of the Linux kernel.

This Linux kernel vulnerability can lead to a root compromise.

This Linux kernel vulnerability was reported by Sendmail, Inc.:
http://www2.sendmail.com/alert/ and
http://sendmail.net/?feed=000607linuxbug

This Linux kernel vulnerability has been publicly discussed in Usenet
newsgroups and mailing lists.


- --------------------------
- --- Temporary Solution ---
- --------------------------

Unfortunately, there are no immediate or temporary workarounds for
this issue.  This issue can only be addressed with the installation
of an RPM.


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

This issue is fixed in 2.2.16 Linux kernel. For more information see:
http://www.linux.org.uk/VERSION/relnotes.2216.html

SGI ProPack 1.4 plans to use the 2.2.16 Linux kernel as its base.
SGI has back-ported the fix to older Linux kernels in ProPack 1.2 and 1.3.
SGI ProPack 1.2 is based on the 2.2.13 Linux kernel.
SGI ProPack 1.3 is based on the 2.2.15 Linux kernel.


   Version           Vulnerable      Patch #      Other Actions
   ---------------   -----------     -------      -------------
   SGI ProPack 1.2      yes           3993
   SGI ProPack 1.3      yes           3991
   SGI ProPack 1.4      no


Patches are available via the web, anonymous FTP and from your SGI
service/support provider.

SGI patches and RPMs for Linux can be found at:
http://support.sgi.com/linux/ and click on patches link and
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/irix/ and ftp://patches.sgi.com/support/relstream/

IRIX Security Patchsets can be found at:
http://www.sgi.com/support/security/ and ftp://sgigate.sgi.com/patches/

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

The primary SGI anonymous FTP site for security information and patches
is sgigate.sgi.com (204.94.209.1). Security information and patches can be
found in the ~ftp/security and ~ftp/patches directories, respectively.

For security and patch management reasons, ftp.sgi.com (mirror of sgigate) lags
behind and does not do a real-time update of ~ftp/security and ~ftp/patches


- ------------------------
- --- Acknowledgments ----
- ------------------------

SGI wishes to thank the users of the Internet Community at large for their
assistance in this matter.


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

If there are questions about this document, email can be sent to
cse-security-alert@sgi.com.

                      ------oOo------

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 information and patches
is sgigate.sgi.com (204.94.209.1).  Security information and patches
are located under the directories ~ftp/security and ~ftp/patches,
respectively.

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

For issues with the patches on the FTP sites, email can be sent to
cse-security-alert@sgi.com.

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

                      ------oOo------

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 SGI as outlined below.

% mail wiretap-request@sgi.com
subscribe wiretap <YourEmailAddress>
end
^d

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.


                      ------oOo------

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

                      ------oOo------

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.


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