Atrium Software Mercur Mailserver POP3 AUTH Remote Buffer Overflow Vulnerability

Risk
High

Date Discovered
10-25-2003

Description
A problem has been reported in MERCUR Mailserver when handling the POP3 AUTH command. This problem may make it possible for an attacker crash the service on a vulnerable system, or gain unauthorized access.

Components Affected
Atrium Software MERCUR Mailserver 3.3 SP2
Atrium Software MERCUR Mailserver 3.3 SP1
Atrium Software MERCUR Mailserver 3.3
Atrium Software MERCUR Mailserver 4.0 1 SP1
Atrium Software MERCUR Mailserver 4.0 1
Atrium Software MERCUR Mailserver 4.2 SP2
Atrium Software MERCUR Mailserver 4.2 SP1
Atrium Software MERCUR Mailserver 4.2

Recommendations
Block external access at the network boundary, unless service is required by external parties.
Filter network traffic of questionable integrity at network perimeters. Prohibit unauthorized traffic through ingress and egress filtering.

Run all software as a non-privileged user with minimal access rights.
Execute all software with the minimal privileges required for functionality. Software that may be prone to attack from malicious users or content should be insulated with additional precautions such as restricted environments.

This vulnerability has been resolved in version 4.2 Service Pack 3a. See referenced vendor advisory for additional details.

Atrium Software MERCUR Mailserver 3.3 SP2:
Atrium Software MERCUR Mailserver 3.3 SP1:
Atrium Software MERCUR Mailserver 3.3:
Atrium Software MERCUR Mailserver 4.0 1 SP1:
Atrium Software MERCUR Mailserver 4.0 1:
Atrium Software MERCUR Mailserver 4.2 SP2:
Atrium Software MERCUR Mailserver 4.2 SP1:
Atrium Software MERCUR Mailserver 4.2:

References
Source: Atrium Software Mercur Mail Server Homepage
URL: http://www.atrium-software.com/mercur/mercur_e.html

Source: MERCUR Mailserver Version 4.2 - Service Pack 3a
URL: http://www.atrium-software.com/mail%20server/pub/mcr42sp3a.html

Credits
Discovery credited to Kostya KORTCHINSKY.

Copyright (c) 2003 by Symantec Corp.
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Disclaimer
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