Check Point Advisories

Microsoft CryptoAPI Object Identifiers Integer Overflow (MS09-056; CVE-2009-2511)

Vulnerability
Protection

Check Point Reference:	CPAI-2009-214
Date Published:	13 Oct 2009
Severity:	High
Last Updated:	Tuesday 07 April, 2015
Source:
Industry Reference:	CVE-2009-2511
Protection Provided by:	Security Gateway R81, R80, R77, R75, R71, R70, R65
Who is Vulnerable?
Vulnerability Description	The CryptoAPI provide services that enable application developers to add encryption/decryption of data, authentication using digital certificates, and encoding to and decoding from Abstract Syntax Notation One (ASN.1) to their Windows-based applications. A spoofing vulnerability has been reported in the Microsoft Windows CryptoAPI component when parsing ASN.1 object identifiers from X.509 certificates. The vulnerability is due to an error in the Windows CryptoAPI that incorrectly parses a null terminator as the end of any values identified by an Object Identifier (OID). This causes the CryptoAPI to only parse part of the actual value. When this partial value has meaning to the end user, this may lead to a situation where an attacker could impersonate another user or system.

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 / R71 / R70 / R65

In the IPS tab, click Protections and find the Microsoft CryptoAPI Object Identifiers Integer Overflow (MS09-056) 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 Client Enforcement Violation.
Attack Information: Microsoft CryptoAPI object identifiers integer overflow (MS09-056)