[ advisories | exploits | discussions | news | conventions | security tools | texts & papers ]
 main menu
- feedback
- advertising
- privacy
- FightAIDS
- newsletter
- news
- read forum
- new topic
- search

- meetings list
- recent additions
- add your info
 top 100 sites
- visit top sites
- sign up now
- members

- add your url
- add domain
- search box
- link to us

- our projects
- free email
 m4d network
- security software
- secureroot
- m4d.com
Home : Advisories : Buffer Overflow in Some Implementations of IMAP Servers

Title: Buffer Overflow in Some Implementations of IMAP Servers
Released by: CERT
Date: 20th July 1998
Printable version: Click here

Hash: SHA1

CERT Advisory CA-98.09.imapd

   Original issue date: July 20, 1998

   Last revised: March 08, 1999   Updated IMAP Server information for



   A complete revision history is at the end of this file.



Buffer Overflow in Some Implementations of IMAP Servers



   The CERT Coordination Center has received reports regarding a

   vulnerability in some implementations of IMAP servers.


   The CERT/CC recommends that anyone running a vulnerable version of

   this software upgrade to the current vendor-recommended version. Until

   you can do so, we suggest disabling the vulnerable IMAP server.


   We will update this advisory as we receive additional information. We

   encourage you to check our web site regularly for updates to this

   advisory that may relate to your site.



I. Description

   The CERT Coordination Center has received reports regarding a buffer

   overflow in some implementations of IMAP servers. The overflow is in

   library code from the University of Washington IMAP server that

   handles SASL server-level authentication. This vulnerability is

   different from the one discussed in CERT Advisory CA-97.09.imap_pop.

   Information about this vulnerability has been posted to various public

   mailing lists and newsgroups.


   All versions of the University of Washington IMAP server prior to the

   final (frozen, non-beta) version of imap-4.1 that support SASL

   server-level authentication are vulnerable. The vulnerability affects

   all University of Washington IMAP4rev1 servers prior to v10.234. Also,

   any v10.234 server that was distributed with Pine 4.0 or any

   imap-4.1.BETA is vulnerable.


   Additionally, the vulnerability is present in other IMAP servers that

   use library code from the University of Washington IMAP server to

   handle SASL server-level authentication.


   IMAP servers that share no code with the University of Washington

   server are not vulnerable.


   Some operating systems ship with a vulnerable version of this software

   installed and enabled by default. Please refer to the Vendor

   Information section below for more information about your vendor.


II. Impact

   Remote intruders can execute arbitrary commands under the privleges of

   the process running the vulnerable IMAP server. If the vulnerable IMAP

   server is running as root, remote intruders can gain root access.


III. Solution



Determine if your version of imapd is vulnerable

       To determine if a system is vulnerable, first telnet to port 143

       on that host. If it is running an IMAP server, the banner will

       show the version. For example:


% telnet host.your.domain.com 143


Connected to host.

Escape character is '^]'.

* OK host.your.domain.com IMAP4rev1 v10.190 server ready

       In the above example, the IMAP server is the University of

       Washington IMAP4rev1 v10.190. Since all University of Washington

       IMAP4rev1 servers prior to v10.234 are vulnerable, the server in

       the above example is vulnerable.

       Please consult the Vendor Information section below for

       information about other vulnerable IMAP servers.



Install the most recent version of imapd

       Obtain and install the most recent version, or patch for your IMAP

       server. Appendix A contains input from vendors who have provided

       information for this advisory.




       If you are unable to upgrade to a version that is not vulnerable,

       we urge you to disable the IMAP server until you are able to

       address the problem.



Appendix A - Vendor Information

   Below is a list of the vendors who have provided information for this

   advisory. We will update this appendix as we receive additional

   information. If you do not see your vendor's name, the CERT/CC did not

   hear from that vendor. Please contact the vendor directly.



IMAP Server Vendors


   This does not affect the Cyrus imapd. Cyrus imapd shares no code with

   the University of Washington imapd.

Esys Corporation

   We are not affected by the problem described in the advisory. We do not

   ship any University of Washington based software at this time. We have

   never shipped any of the IMAP 4.x software from the University of



   No ISOCOR products are affected by this problem. The N-PLEX implementation

   shares no code with the University of Washington imapd.

Microsoft Corporation

   No Microsoft products are affected by this problem.

NEC Corporation

   The University of Washington imapd is shipped with our product

   "Mobilenet/IMAP" and so it is vulnerable.


   Netscape Messaging Server 3.55 and before are susceptible to this

   vulnerability. However, it should be noted that Netscape Messaging

   Server (any version) does NOT run as root and therefore, the exposure

   is much more limited than the University of Washington example.

   Regardless, we have released a patch available at 

   http://help.netscape.com/products/server/messaging which

   addresses this vulnerability.

Sun Microsystems

   Please refer to Sun Microsystems, Inc. Security Bulletin, "IMAP",

   Number: 00177, distributed October 2, 1998 for additional information

   relating to this vulnerability.

   Patches and Checksums are available to all Sun customers via World Wide

   Web at:


   Sun security bulletins are available via World Wide Web at:


University of Washington

   A security problem has been detected with the University of Washington

   IMAP server that is included in the Pine 4.00 distribution. This will

   be fixed in the forthcoming Pine 4.01 maintenance release. Until then,

   if you are using the UW IMAP server, please update it with the

   following distribution:


   This vulnerability affects all IMAP4rev1 servers prior to

   v10.234. v10.234 may or may not be vulnerable; if it came from Pine

   4.00 or from any imap-4.1.BETA then it is vulnerable. IMAP2bis

   servers are immune. This problem is also fixed in the imap-4.2

   toolkit, which is tentatively expected to be released in

   conjunction with Pine 4.01. Any IMAP4rev1 server whose version

   starts with "v11" will be immune.



Operating System Vendors

Berkeley Software Design, Inc.

   The version of IMAP shipped with BSD/OS 2.1 and 3.0/3.1 is the older

   version which does not include the vulnerability.

   The version of IMAP which will be included in the upcoming 4.0 release

   has been updated to include the security fixes.

Caldera Linux

   Caldera: releasing patched imap-4.1; will release imap-4.2 as soon as

            it becomes available.

   URL:     http://ftp.caldera.com/pub/OpenLinux/updates/1.2/010

   6df741b4217f03bf773b54509a7d283a  imap-4.1.BETA-5.i386.rpm

   d3526121c68b611524fc72746204d752  imap-4.1.BETA-5.src.rpm

Compaq Computer Corporation

   (c) Copyright 1994, 1995, 1996, 1997, 1998 Compaq Computer Corporation.

   All rights reserved.

   SOURCE: Compaq Computer Corporation

           Compaq Services

           Software Security Response Team USA

   This reported problem is not present for the as shipped,

   Compaq's Digital ULTRIX or Compaq's Digital UNIX

   Operating Systems Software.

                             - Compaq Computer Corporation

Data General

   We are investigating. We will provide an update when our

   investigation is complete.


   FreeBSD does not ship default with imap. However, there is a version

   of imapd from Washington University in the FreeBSD ports collections,

   known as imap-uw.

   If anyone is using the imap port, we suggest fetching the latest revision

   of imap and manually install it, or wait until the FreeBSD port is updated

   and reinstall imap-uw using the ports system.

   You can check the ports status at:



   Our operating system, UXP/V, does not support imapd. Therefore, it is

   not vulnerable to the above vulnerability.

Hewlett-Packard Company

   HP does not ship the University of Washington IMAP server.

IBM Corporation

   The version of imapd shipped with AIX 4.2 and 4.3 is vulnerable.  We

   are currently working on the following fixes which will be available


     AIX 3.2.x:  imapd not shipped (not vulnerable)

     AIX 4.1.x:  imapd not shipped (not vulnerable)

     AIX 4.2.x:  IX80446

     AIX 4.3.x:  IX80447

   To Order


     APARs may be ordered using Electronic Fix Distribution (via FixDist)

     or from the IBM Support Center.  For more information on FixDist,

     reference URL:


     or send e-mail to aixserv@austin.ibm.com with a subject of "FixDist".

   IBM and AIX are registered trademarks of International Business Machines



   NetBSD does not ship the UW imapd daemon in its standard or development

   operating system releases. Our optional package system also does not

   include it at this time.


   OpenBSD has never shipped an imap daemon.

Red Hat Linux

   Serious security problems have been found in all versions of imap shipped

   with Red Hat Linux. If "rpm -q imap" shows that imap is installed on

   your system, please upgrade to these new imap releases immediately, or

   remove imap by running "rpm -e imap". Note that Red Hat's imap package

   also provides a POP server, so only remove it if you don't need to provide

   POP services.

   Thanks to everyone who helped find these problems, Olaf Kirch in particular.

   Red Hat 5.0 and 5.1



   rpm -Uvh http://ftp.redhat.com/updates/5.0/i386/imap-4.1.final-1.i386.rpm


   rpm -Uvh http://ftp.redhat.com/updates/5.0/alpha/imap-4.1.final-1.alpha.rpm


   rpm -Uvh http://ftp.redhat.com/updates/5.0/sparc/imap-4.1.final-1.sparc.rpm

   Red Hat 4.2



   rpm -Uvh http://ftp.redhat.com/updates/4.2/i386/imap-4.1.final-0.i386.rpm


   rpm -Uvh http://ftp.redhat.com/updates/4.2/alpha/imap-4.1.final-0.alpha.rpm


   rpm -Uvh http://ftp.redhat.com/updates/4.2/sparc/imap-4.1.final-0.sparc.rpm

The Santa Cruz Operation, Inc.

   The following SCO products are vulnerable:

   - SCO UnixWare 7

   SCO OpenServer 5.0, SCO CMW+ 3.0, SCO Open Desktop/Open Server 3.0,   and

   UnixWare 2.1 is not vulnerable as University of Washington imapd   is not

   included in these platforms.

   Binary versions of University of Washington imapd will be available

   shortly from the SCO ftp site:

   http://ftp.sco.com/SSE/sse014.ltr - cover letter

   http://ftp.sco.com/SSE/sse014.tar.Z - replacement binaries

   This fix is a binary for the following SCO operating systems:

   - SCO UnixWare 7

   For the latest security bulletins and patches for SCO products,

   please refer to http://www.sco.com/security/.

Silicon Graphics Inc.

   Please refer to Silicon Graphics Inc. Security Advisory, "University

   of Washington imapd daemon Vulnerability," Number: 19980802-01-I,

   distributed August 6, 1998 for additional information relating to this


   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.



   The CERT Coordination Center thanks Olaf Kirch of Caldera Linux for

   discovering and reporting the vulnerability. Additionally, we would

   like to thank Mark Crispin and Lori Stevens of the University of

   Washington for providing technical details and support in the

   development of the advisory.



   This document is available from:




CERT/CC Contact Information

   Email: cert@cert.org

          Phone: +1 412-268-7090 (24-hour hotline)

          Fax: +1 412-268-6989

          Postal address:

          CERT Coordination Center

          Software Engineering Institute

          Carnegie Mellon University

          Pittsburgh PA 15213-3890



   CERT personnel answer the hotline 08:00-20:00 EST(GMT-5) / EDT(GMT-4)

   Monday through Friday; they are on call for emergencies during other

   hours, on U.S. holidays, and on weekends.


Using encryption

   We strongly urge you to encrypt sensitive information sent by email.

   Our public PGP key is available from http://www.cert.org/CERT_PGP.key.

   If you prefer to use DES, please call the CERT hotline for more



Getting security information

   CERT publications and other security information are available from

   our web site http://www.cert.org/.


   To be added to our mailing list for advisories and bulletins, send

   email to cert-advisory-request@cert.org and include SUBSCRIBE

   your-email-address in the subject of your message.


   Copyright 1999 Carnegie Mellon University.

   Conditions for use, disclaimers, and sponsorship information can be

   found in http://www.cert.org/legal_stuff.html.


   * "CERT" and "CERT Coordination Center" are registered in the U.S.

   Patent and Trademark Office




   Any material furnished by Carnegie Mellon University and the Software

   Engineering Institute is furnished on an "as is" basis. Carnegie

   Mellon University makes no warranties of any kind, either expressed or

   implied as to any matter including, but not limited to, warranty of

   fitness for a particular purpose or merchantability, exclusivity or

   results obtained from use of the material. Carnegie Mellon University

   does not make any warranty of any kind with respect to freedom from

   patent, trademark, or copyright infringement.



   Revision history

Mar. 08, 1999  Updated IMAP Server information for ISOCOR.

Nov. 16, 1998  Updated patch information for Sun Microsystems, Inc.

Sept. 4, 1998  Added vendor information for Silicon Graphics, Inc.

Aug. 14, 1998  Added vendor information for Microsoft Corporation.


Version: PGP for Personal Privacy 5.0

Charset: noconv





(C) 1999-2000 All rights reserved.