2000313 : TCP OS fingerprint

Low RiskLow Risk

Quick Links

Event description Jump to the top of this document

A remote attacker may be attempting to identify the victim's operating system by sending unusual combinations of TCP flags to see how the system responds. This information can help the attacker determine those weaknesses that reside on the system, and provide information to assist in performing further attacks.

Products that have this security check Jump to the top of this document

TCP_OS_Fingerprint

This signature detects unusual TCP flag combinations that may indicate an attacker's attempt to guess the operating system used by a remote TCP stack. Flag combinations that trigger this signature include SYN|FIN, FIN|PUSH|URG, PUSH, (null), or use of the TCP reserved bits as defined by RFC793.

False Positive:A false positive is possible if these flag combinations are being issued for legitimate reasons (RFC2481).

Affected platforms Jump to the top of this document

How to remove this vulnerability Jump to the top of this document

Ensure that your personal firewall, operating system, and programs are up-to-date in order to minimize the threat of a system compromise.

References Jump to the top of this document

Information about this document Jump to the top of this document

The information contained in this document may change without notice, and may have been altered or changed if you have received it from a source other than Internet Security Systems. Use of this information constitutes acceptance for use in an "AS IS" condition, without warranties of any kind, and any use of this information is at the user's own risk. Internet Security Systems disclaims all warranties, either expressed or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Internet Security Systems be liable for any damages whatsoever, including direct, indirect, incidental, consequential or special damages, arising from the use or dissemination hereof, even if Internet Security Systems has been advised of the possibility of such damages.

Copyright © 1997 – 2009 IBM Internet Security Systems. All rights reserved.

This page was created on Thu Jun 11 09:07:00 2009