AUSCERT External Security Bulletin Redistribution

              ESB-98.128 -- SGI Security Advisory 19980802-01-I
             University of Washington imapd daemon Vulnerability
                               07 August 1998


Silicon Graphics Inc. has released the following advisory concerning a
buffer overflow vulnerability in fw_imap daemon, which is the version of
IMAP server that they distribute.  This vulnerability may allow remote
users to obtain root access on systems running a vulnerable IMAP server.
Intruders do not need access to an account on the system to exploit this

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


                Silicon Graphics Inc. Security Advisory

        Title:   University of Washington imapd daemon Vulnerability
        Title:   CERT CA-98.09
        Number:  19980802-01-I
        Date:    August 6, 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.

As a followup to the CERT(sm) Advisory CA-98.09 "Buffer Overflow in Some
Implementations of IMAP Servers", Silicon Graphics has investigated and
provides the following information.

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

The IMAP and POP provides users with an alternative means to process and
retrieve their email.

CERT has reported that a buffer overflow vulnerability has been discovered
in certain versions of IMAP servers based on University of Washington imapd
daemon which can allow remote users to obtain root access.

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.

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

Silicon Graphics distributes a freeware University of Washington imapd
daemon called fw_imap which is available from the web via

The University of Washington imapd daemon 4.1.BETA v10.234 and prior
versions are vulnerable.

This vulnerability was reported in CERT(sm) Advisory CA-98.09.

This vulnerability has been publically discussed in Usenet newsgroups
and mailing lists.

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

Although new releases of University of Washington imapd daemon may be
available to fix this issue, it is realized that there may be situations
where installing the new release immediately may not be possible.

To determine if a system is vulnerable to this problem and to remove
the programs that are believed to be vulnerable, use the following steps.

     1) Check to see if the vulnerable subsystem is installed.
        4.1-BETA and prior of fw_imap are vulnerable.

        % versions -b fw_imap
           Name           Date      Description
        I  fw_imap        07/31/98  imap-4.1.BETA U. of Washington
                                    POP2/POP3/IMAP4 daemons

     2) Become the root user on the system.

        % /bin/su -

     3) Remove the vulnerable subsystem.

        # versions remove fw_imap

     4) Return to previous level.

        # exit

        When possible, install an updated version of University of
        Washington imapd daemon.

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

No Silicon Graphics patches are available for freeware software.

As freeware software, all reasonable efforts will be made to address
the issue in future releases of the Silicon Graphics Freeware distribution.
Updates to IRIX freeware software will be hosted at http://freeware.sgi.com/

An update to imapd daemon can be found at University of Washington ftp server:

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

Silicon Graphics wishes to thank the CERT Coordination Center for their
assistance in this matter.

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

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


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 (  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

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


Silicon Graphics 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>

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.


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


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, Silicon
  Graphics is appropriately credited and the document retains and
  includes its valid PGP signature.

Version: 2.6.2

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