Risk
Medium
Date Discovered
June 14, 2005
Description
Microsoft Internet Security and Acceleration (ISA) server is prone to a policy bypass vulnerability. Reports indicate that the issue manifests when a Microsoft ISA server is utilizing the 'NetBIOS (all)' predefined filter.
A remote attacker may leverage this vulnerability to successfully make NetBIOS connections to NetBIOS based services that exist on a target ISA server.
Technologies Affected
- Microsoft ISA Server 2000
- Microsoft ISA Server 2000 Enterprise Edition
- Microsoft ISA Server 2000 Enterprise Edition SP1
- Microsoft ISA Server 2000 Enterprise Edition SP2
- Microsoft ISA Server 2000 FP1
- Microsoft ISA Server 2000 SP1
- Microsoft ISA Server 2000 SP2
Recommendations
Block external access at the network boundary, unless external parties require service.
Network access controls should be deployed to limit remote access to NetBIOS services on the affected computer. This may reduce the risk associated with this vulnerability.Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy an intrusion detect sensor. Flag on anomalous NetBIOS traffic, audit logs regularly for indications of potentially malicious attacks and adjust policies accordingly.
Microsoft has released a fix to address this issue.
Credits
The vendor reported this issue.
Copyright © 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
secure@symantec.com.
Disclaimer
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
secure@symantec.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.
