IBM-ERS Security Vulnerability Alert: AIX V3 rmail vulnerability

IBM-ERS Security Vulnerability Alert: AIX V3 rmail vulnerability

Post by Dave Cur » Wed, 17 Apr 1996 04:00:00


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                           EMERGENCY RESPONSE SERVICE
                          SECURITY VULNERABILITY ALERT

16 April 1996 16:00 GMT                          Number: ERS-SVA-E01-1996:003.1
                             VULNERABILITY  SUMMARY

VULNERABILITY:  Vulnerability in the IBM AIX "rmail" program.

PLATFORMS:      AIX Version 3 (Version 4 does not contain this vulnerability).

SOLUTION:       Take one of the actions described below.

THREAT:         A user can gain unauthorized access to another user's mail.

                              DETAILED INFORMATION

I. Description

There is a potential security exposure in the "rmail" program on Version 3
of the IBM AIX operating system.

Version 4 of AIX does not contain this vulnerability.

II. Impact

A user with knowledge of this vulnerability can exercise it to obtain
unauthorized access to another user's electronic mail.

III. Solutions

The IBM AIX Response Team recommends two solutions to this problem:

1. Log in to the workstation as "root" and issue the command:

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

2. Apply the following APAR to your system once the APAR is available:

        APAR - IX57680

The first solution should be applied immediately to remove the vulnerability
to your system.  Once the APAR is available, you should also apply the second

IV. Acknowledgements

IBM-ERS would like to thank the IBM AIX Response Team for providing the
information contained in this alert.


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Copyright 1996 International Business Machines Corporation.

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