March 14, 2006
Microsoft Excel is prone to a remote code-execution vulnerability. This issue may be triggered when a malformed Excel document is opened.
- Avaya Modular Messaging (MAS) 3.0.0
- Microsoft Excel 2000
- Microsoft Excel 2000 SP2
- Microsoft Excel 2000 SP3
- Microsoft Excel 2000 SR1
- Microsoft Excel 2002
- Microsoft Excel 2002 SP1
- Microsoft Excel 2002 SP2
- Microsoft Excel 2002 SP3
- Microsoft Excel 2003
- Microsoft Excel 2003 SP1
- Microsoft Excel 2004 for Mac
- Microsoft Excel Viewer 2003
- Microsoft Excel x for Mac
- Nortel Networks Enterprise Network Management System
- Nortel Networks IP softphone 2050
- Nortel Networks MCS 5100 3.0.0
- Nortel Networks MCS 5200 3.0.0
- Nortel Networks Optivity Telephony Manager (OTM)
Run all software as a nonprivileged user with minimal access rights.
All non-administrative tasks should be performed as an unprivileged user with minimal access rights.
Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy NIDS to monitor network traffic for signs of suspicious or anomalous activity. This may help detect malicious actions that an attacker may take after successfully exploiting vulnerabilities in applications. Review all applicable logs regularly.
Do not accept or execute files from untrusted or unknown sources.
Users should never accept files from untrusted or unknown sources, because they may be malicious in nature. Avoid opening email attachments from unknown or questionable sources.
Do not follow links provided by unknown or untrusted sources.
Users should avoid websites of questionable integrity. Never follow links supplied by unknown or untrusted sources.
Implement multiple redundant layers of security.
Since this issue may be leveraged to execute code, we recommend memory-protection schemes, such as non-executable stack/heap configurations and randomly mapped memory segments. This tactic may complicate exploitation of memory-corruption vulnerabilities.
Microsoft has released fixes to address this vulnerability in supported versions of the affected software. Avaya has released advisory ASA-2006-069 to identify vulnerable Avaya products. Avaya advises customers to apply patches released by Microsoft. Please see the references for more information.
Discovery is credited to Arnaud Dovi aka 'class101'.
© 1995- Symantec Corporation
Permission to redistribute this alert electronically is granted as long as it is not edited in any way unless authorized by Symantec Security Response. Reprinting the whole or part of this alert in any medium other than electronically requires permission from firstname.lastname@example.org.
The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information.
Symantec, Symantec products, Symantec Security Response, and email@example.com are registered trademarks of Symantec Corp. and/or affiliated companies in the United States and other countries. All other registered and unregistered trademarks represented in this document are the sole property of their respective companies/owners.