Check Point Advisories

Squid SSL-Bump Denial of Service

Vulnerability
Protection

Check Point Reference:	CPAI-2015-1300
Date Published:	16 Nov 2015
Severity:	High
Last Updated:	Monday 07 December, 2015
Source:	Squid Project
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?	Squid Project Squid Prior to 3.5.9
Vulnerability Description	A denial-of-service vulnerability exists in Squid. The vulnerability is due to integer overflow and input validation errors in Squid when processing TLS messages. A remote, unauthenticated attacker can exploit this vulnerability by sending a specially crafted Client or Server Hello message, which when parsed triggers the vulnerability; the vulnerable application consumes an uncontrolled amount of resource and does not respond to requests, leading to a denial-of-service condition.

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 R80 / R77 / R75

In the IPS tab, click Protections and find the Squid SSL-Bump Denial of Service 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: Proxy Server Enforcement Violation.
Attack Information: Squid SSL-Bump Denial of Service