Subject: IRIX mail(1)/rmail(1M)/sendmail(1M) Security Vulnerabilities

From: SGI Security Coordinator <[email-masked]>
Date: Thu, 18 Jun 1998 15:04:25 -0700

DISTRIBUTION RESTRICTIONS - NONE - FOR PUBLIC RELEASE

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

______________________________________________________________________________
                Silicon Graphics Inc. Security Advisory

        Title:   IRIX mail(1)/rmail(1M)/sendmail(1M) Security Vulnerabilities
        Title:   CERT CA-96.20
        Number:  19980604-01-PX
        Date:    June 18, 1998
______________________________________________________________________________

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

Silicon Graphics 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
Silicon Graphics 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 ---
- ------------------------

This advisory covers two security issues that were publically reported as
two different issues.  Both these issues have been addressed together
as one issue by Silicon Graphics.

The first security issue involves mail(1)/rmail(1M) programs.
The mail(1) program, also know as mail_att, is used to read or send email.
The rmail(1M) program is usually invoked by uux(1C) to receive email
via UUCP(1C).

Several security vulnerabilities were discovered in mail(1)/rmail(1M) that
allow any local user with access to mail(1) and rmail(1M) programs to access
or modify any file that is owned by the mail group(4).

The second security issue involves sendmail(1M).
The sendmail(1M) program is used to deliver and receive email.
On a fully patched IRIX system, the default version of sendmail is 8.6.12.

Several vulnerabilities have been found in sendmail 8.7.5 and lower which are
referenced and documented in CERT CA-96.20 and can be found at:

http://www.cert.org/advisories/CA-96.20.sendmail_vul.html

Silicon Graphics Inc. 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 IRIX.

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

The mail(1)/rmail(1M)/sendmail(1M) programs are installed by default on IRIX.

A user account on the vulnerable system is required in order to exploit
mail(1)/rmail(1M) locally and remotely.

A local user account is not needed to exploit the sendmail(1M) program locally
and remotely.

These vulnerabilities have been publically discussed in Usenet newsgroups
and mailing lists.

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

Although patches are available for this issue, it is realized that
there may be situations where installing the patches immediately may
not be possible.

The steps below can be used to remove the vulnerability by removing
the setgid permissions of the mail(1)/rmail(1M) programs.

There are no workarounds for sendmail 8.6.12 vulnerabilities.
The sendmail(1M) program must be disabled or the patches need to be installed
to upgrade it to sendmail 8.8.8.

     1) Become the root user on the system.

                % /bin/su -
                Password:
                #

     2) Remove the setgid permissions on the vulnerable programs.

                # /bin/chmod 555 /usr/bin/mail
                # /bin/chmod 555 /usr/bin/rmail

     4) Verify the new permissions on the program.
        Note that the program size may be different depending on release.

                # ls -al /usr/bin/mail /usr/bin/rmail

                -r-xr-xr-x    1 root  mail  53024 Feb 12  1996 mail
                -r-xr-xr-x    1 root  mail  14216 May 16  1996 rmail

     5) Disable the vulnerable sendmail(1M) program.

                # chkconfig sendmail off
                # /etc/init.d/mail stop

     5) Return to previous user level.

                # exit
                %

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

These patches fix the rmail(1)/mail(1M) security vulnerabilities and upgrade
sendmail(1M) to version 8.8.8.

   OS Version     Vulnerable?     Patch #      Other Actions
   ----------     -----------     -------      -------------

   IRIX 3.x          yes          not avail    Note 1, 2 & 3
   IRIX 4.x          yes          not avail    Note 1, 2 & 3
   IRIX 5.0.x        yes          not avail    Note 1, 2 & 3
   IRIX 5.1.x        yes          not avail    Note 1, 2 & 3
   IRIX 5.2          yes          not avail    Note 1, 2 & 3
   IRIX 5.3          yes           2309
   IRIX 6.0.x        yes          not avail    Note 1, 2 & 3
   IRIX 6.1          yes          not avail    Note 1, 2 & 3
   IRIX 6.2          yes           2231
   IRIX 6.3          yes           2310
   IRIX 6.4          yes           2310
   IRIX 6.5          no

   NOTES

     1) Upgrade to currently supported IRIX operating system.
     2) See "Temporary Solution" section for a workaround.
     3) Unsupported by SGI, "freeware" sendmail distributions can be found at
        http://www.sendmail.org/

Patches are available via anonymous FTP and your service/support provider.

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

                 ##### Patch File Checksums ####

The actual patch will be a tar file containing the following files:

Filename:                 README.patch.2231
Algorithm #1 (sum -r):    29635 8 README.patch.2231
Algorithm #2 (sum):       61238 8 README.patch.2231
MD5 checksum:             93F6B8811CE2576475316A2B4642FFA5

Filename:                 patchSG0002231
Algorithm #1 (sum -r):    52080 2 patchSG0002231
Algorithm #2 (sum):       7506 2 patchSG0002231
MD5 checksum:             513D5729D2356C79D5E397863803F5D5

Filename:                 patchSG0002231.eoe_man
Algorithm #1 (sum -r):    31776 69 patchSG0002231.eoe_man
Algorithm #2 (sum):       10533 69 patchSG0002231.eoe_man
MD5 checksum:             A6E76331FE9611319D137B260CF0D76E

Filename:                 patchSG0002231.eoe_sw
Algorithm #1 (sum -r):    13889 687 patchSG0002231.eoe_sw
Algorithm #2 (sum):       24064 687 patchSG0002231.eoe_sw
MD5 checksum:             8228192A12048ACD78AB8F262A006A33

Filename:                 patchSG0002231.idb
Algorithm #1 (sum -r):    07552 6 patchSG0002231.idb
Algorithm #2 (sum):       29565 6 patchSG0002231.idb
MD5 checksum:             4B4CA561990D6CCE21C322650DB5E4D6
Filename:                 README.patch.2309
Algorithm #1 (sum -r):    32975 9 README.patch.2309
Algorithm #2 (sum):       60467 9 README.patch.2309
MD5 checksum:             5848AB770B8EA81FA196FFCC12082056

Filename:                 patchSG0002309
Algorithm #1 (sum -r):    56282 4 patchSG0002309
Algorithm #2 (sum):       42072 4 patchSG0002309
MD5 checksum:             14649EBE949F464B28E17FA03F001AC8

Filename:                 patchSG0002309.eoe1_man
Algorithm #1 (sum -r):    57312 69 patchSG0002309.eoe1_man
Algorithm #2 (sum):       39389 69 patchSG0002309.eoe1_man
MD5 checksum:             7DA3680EC4CBB635265E349E9603C58B

Filename:                 patchSG0002309.eoe1_sw
Algorithm #1 (sum -r):    28257 688 patchSG0002309.eoe1_sw
Algorithm #2 (sum):       30302 688 patchSG0002309.eoe1_sw
MD5 checksum:             250B98DC7C4207094818C2C2F2C37254

Filename:                 patchSG0002309.idb
Algorithm #1 (sum -r):    53181 6 patchSG0002309.idb
Algorithm #2 (sum):       30341 6 patchSG0002309.idb
MD5 checksum:             57CFB3DE7EACE6CEC75A8C1EECBE6E6D
Filename:                 README.patch.2310
Algorithm #1 (sum -r):    30227 8 README.patch.2310
Algorithm #2 (sum):       53644 8 README.patch.2310
MD5 checksum:             109285169451B313A39E157801EF77A5

Filename:                 patchSG0002310
Algorithm #1 (sum -r):    52429 2 patchSG0002310
Algorithm #2 (sum):       57083 2 patchSG0002310
MD5 checksum:             A7FD0C1AEDD8D2F75FE72232E71B6483

Filename:                 patchSG0002310.eoe_man
Algorithm #1 (sum -r):    07011 69 patchSG0002310.eoe_man
Algorithm #2 (sum):       10532 69 patchSG0002310.eoe_man
MD5 checksum:             F0003330AB4E323744B6015182E0F68A

Filename:                 patchSG0002310.eoe_sw
Algorithm #1 (sum -r):    64113 692 patchSG0002310.eoe_sw
Algorithm #2 (sum):       13768 692 patchSG0002310.eoe_sw
MD5 checksum:             DA6870AD18DBC691424B5E52B32DF18B

Filename:                 patchSG0002310.idb
Algorithm #1 (sum -r):    07855 6 patchSG0002310.idb
Algorithm #2 (sum):       28233 6 patchSG0002310.idb
MD5 checksum:             6836E4720A7F7779681EB0486D8AAD5C

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

Silicon Graphics wishes to thank the CERT Coordination Center and the users
of the Internet Community at large for their assistance in this matter.

- ------------------------------------------------------------
- ---- Silicon Graphics Inc. Security Information/Contacts ---
- ------------------------------------------------------------

If there are questions about this document, email can be sent to
[email-masked].

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

Silicon Graphics 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 Silicon Graphics Security Headquarters Web page is
accessible at the URL http://www.sgi.com/Support/security/security.html.

For issues with the patches on the FTP sites, email can be sent to
[email-masked].

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

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

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subscribe wiretap <YourEmailAddress>
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                      ------oOo------

Silicon Graphics provides a comprehensive customer World Wide Web site.
This site is located at http://www.sgi.com/Support/security/security.html.

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

For reporting *NEW* SGI security issues, email can be sent to
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______________________________________________________________________________
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