Check Point Advisories

Squid HTTP Response Processing Denial of Service (CVE-2016-3948)

Vulnerability
Protection

Check Point Reference:	CPAI-2016-0362
Date Published:	19 May 2016
Severity:	High
Last Updated:	Sunday 29 May, 2016
Source:	Squid Project SQUID-2016:4
Industry Reference:	CVE-2016-3948
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?	Squid Project Squid 3.2.x and prior Squid Project Squid 3.3.x Squid Project Squid 3.4.x Squid Project Squid 3.5.x prior to 3.5.16 Squid Project Squid 4.0.x prior to 4.0.8
Vulnerability Description	The vulnerability is due to improper bounds checking while processing HTTP responses. A remote, unauthenticated attacker can exploit this vulnerability by returning crafted HTTP responses to the vulnerable proxy server. Successful exploitation of the vulnerability could lead to denial-of-service conditions.

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 HTTP Response Processing 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 HTTP Response Processing Denial of Service