Check Point Advisories

Non-Telnet Traffic Over Port 23

Vulnerability
Protection

Check Point Reference:	CPAI-2012-075
Date Published:	27 Feb 2012
Severity:	N/A
Last Updated:	Wednesday 06 May, 2015
Source:
Protection Provided by:	Security Gateway R77, R75, R71, R70
Who is Vulnerable?
Vulnerability Description	TCP Port 23 is normally used to transfer Telnet traffic. Non-Telnet traffic over this port may be used for malicious purposes. Many applications scan for open Telnet ports for malicious purposes. Non-Telnet traffic over port 23 may indicate an attempt to pass malicious traffic to or outside the network. There are cases in which certain traffic, although not intended for malicious use, is very unsafe, since it may transfer shellcode which is undetectable by IPS.

Protection Overview

This protection will detect and block non-Telnet traffic over port 23.

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 / R71 / R70

In the IPS tab, click Protections and find the Non-Telnet Traffic Over Port 23 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: Telnet Enforcement Violation.
Attack Information: Non-Telnet traffic over port 23