Check Point Advisories

PHP Exif_Process_User_Comment Null Pointer Dereference (CVE-2016-6292)

Vulnerability
Protection

Check Point Reference:	CPAI-2016-0717
Date Published:	21 Aug 2016
Severity:	Medium
Last Updated:	Monday 05 June, 2017
Source:	PHP Group
Industry Reference:	CVE-2016-6292
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?	PHP Group PHP prior to 5.5.38 PHP Group PHP prior to 5.6.24 PHP Group PHP prior to 7.0.9
Vulnerability Description	A denial of service vulnerability exists in the Exif module of PHP. The vulnerability is due to a null pointer dereference in exif_process_user_comment when trying to handle JIS encoded user comment Exif tags when multi-byte string support is enabled in PHP. A remote, unauthenticated attacker can exploit this vulnerability by having the target PHP application process Exif data on a maliciously crafted image. Successful exploitation would cause the PHP interpreter to crash, 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 PHP Exif_Process_User_Comment Null Pointer Dereference 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: Web Server Enforcement Violation.
Attack Information: PHP Exif_Process_User_Comment Null Pointer Dereference