Check Point Advisories

TCP Off Path Sequence Number Inference

Vulnerability
Protection

Check Point Reference:	CPAI-2013-2938
Date Published:	30 Sep 2013
Severity:	Low
Last Updated:	Monday 06 January, 2025
Source:
Protection Provided by:	Security Gateway R75
Who is Vulnerable?	Network devices.
Vulnerability Description	An Internet connection hijack vulnerability has been reported in network devices.
Vulnerability Details	The vulnerability is due to a design flaw which allows an off-path attacker to identify the current sequence range of a TCP connection. The attack does not require attackers to have a man-in-the-middle capability. Successful exploitation could allow an attacker to inject data or hijack the TCP connection.

Protection Overview

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

This protection is only applicable for IPS gateway version R75.30 and higher.
In order for the protection to be activated, update your product to the latest update. For information on how to update , go to SBP-2006-05, Protection tab and select the version of your choice.

Security Gateway R75 / R71 / R70

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

SmartView Tracker will log the following entries:
Attack Name: TCP Enforcement Violation
Attack Information: TCP Off Path Sequence Number Inference