Check Point Advisories

TCP Off-Path Sequence Inference

Vulnerability
Protection

Check Point Reference:	CPAI-2013-2938
Date Published:	30 Sep 2013
Severity:	Low
Last Updated:	Sunday 03 November, 2013
Source:
Protection Provided by:	Security Gateway R77, R75
Who is Vulnerable?
Vulnerability Description	The vulnerability is due to a design flaw which allows an off-path attacker to identify the current sequence range of a TCP connection. Successful exploitation could allow an attacker to inject data or hijack the TCP connection. This protection is only applicable for IPS gateway version R75.30 and higher.

Protection Overview

This protection will detect and block attempts to exploit this vulnerability.

In order for the protection to be activated, update your Security Gateway product to the latest IPS update. For information on how to update IPS, go to SBP-2006-05, click on Protection tab and select the version of your choice.

Security Gateway R77 / R75

In the IPS tab, click Protections and find the TCP Off-Path Sequence Inference protection using the Search tool and Edit the protection's settings.
Install policy on all Security Gateways.

This protection's log will contain the following information:

Attack Name: TCP Enforcement Violation.
Attack Information: TCP Off-Path Sequence Inference