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CA-93:11                        CERT Advisory
                                August 9, 1993
                  UMN UNIX gopher and gopher+ Vulnerabilities

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The CERT Coordination Center has received information concerning
vulnerabilities in versions of the UMN UNIX gopher and gopher+ server and
client available before August 6, 1993.  Vulnerable versions were available on
boombox.micro.umn.edu:/pub/gopher/Unix/gopher1.12s.tar.Z,
boombox.micro.umn.edu:/pub/gopher/Unix/gopher2.03.tar.Z, and many other
anonymous FTP sites mirroring these software versions.

We strongly recommend that any site using versions of UMN UNIX gopher
and gopher+ dated prior to August 6, 1993 (including version 1.12, 1.12s,
2.0+, 2.03, and all earlier versions) immediately take corrective action.

If you have further questions regarding UMN UNIX gopher or gopher+ software, 
send e-mail to: gopher@boombox.micro.umn.edu 
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I.   Description

     Several vulnerabilities have been identified in UMN UNIX gopher and 
     gopher+ when configured as a server or public access client.
 
     Intruders are known to have exploited these vulnerabilities to obtain 
     password files.  Other actions may also have been taken by intruders
     exploiting these vulnerabilities.  CERT has already contacted those
     sites currently known to have been victims of these activities. However, 
     sites may want to check for weak passwords, or consider changing 
     passwords, after installing the new gopher software.

II.  Impact

     Anyone (remote or local) can potentially gain unrestricted access 
     to the account running the public access client, thereby permitting 
     them to read any files accessible to this account (possibly including 
     /etc/passwd or other sensitive files).

     In certain configurations, anyone (remote or local) can potentially
     gain access to any account, including root, on a host configured as a
     server running gopherd.
 
III. Solution 

     Affected sites should consider disabling gopherd service and public gopher
     logins until they have installed the new software.

     New versions of the UMN UNIX gopher and gopher+ software have been 
     released that provide bug fixes and correct these security problems.  
     Sites can obtain these new versions via anonymous FTP from 
     boombox.micro.umn.edu (134.84.132.2). The files are located in:

     Filename                                Size     Checksum
     --------                                ------   -----------
     Gopher:
     /pub/gopher/Unix/gopher1.12S.tar.Z      306872   46311   300
     Gopher+:
     /pub/gopher/Unix/gopher2.04.tar.Z       294872   29411   288

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The CERT Coordination Center wishes to thank Matt Schroth, Williams College, 
and others for informing us of these vulnerabilities.  We would also like to 
thank Paul Lindner, University of Minnesota, for his quick response to these 
problems.
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If you believe that your system has been compromised, contact the CERT
Coordination Center or your representative in FIRST (Forum of Incident
Response and Security Teams).

Internet E-mail: cert@cert.org
Telephone: 412-268-7090 (24-hour hotline)
           CERT personnel answer 8:30 a.m.-5:00 p.m. EST(GMT-5)/EDT(GMT-4),
           and are on call for emergencies during other hours.

CERT Coordination Center
Software Engineering Institute
Carnegie Mellon University
Pittsburgh, PA 15213-3890

Past advisories, information about FIRST representatives, and other information
related to computer security are available for anonymous FTP from cert.org
(192.88.209.5).

