Check Point Advisories

MIT Kerberos V5 KDC krb5_unparse_name Heap Overflow (CVE-2005-1175)

Vulnerability
Protection

Check Point Reference:	CPAI-2005-266
Date Published:	29 Jun 2010
Severity:	Critical
Last Updated:	Tuesday 29 June, 2010
Source:
Industry Reference:	CVE-2005-1175
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?
Vulnerability Description	Kerberos is a protocol that allows for the negotiation of an authenticated, and optionally encrypted, communication channel between two points on a network. MIT Kerberos V5 is an implementation of this protocol. There exists a single byte heap overflow vulnerability in the MIT Kerberos V5 Key Distribution Center (KDC) implementation. The vulnerability is caused due to an improper boundary checking in krb5_unparse_name function, and can result in a single byte overflow of a heap buffer. An unauthenticated remote attacker can leverage this vulnerability to cause a denial of service or to execute arbitrary code, potentially compromising an entire Kerberos realm. In case of an attack where code injection is not successful, the Key Distribution Center (KDC) server will terminate abnormally. Consequently, the functionality of servers and workstations in the affected Kerberos Realm is interrupted, creating a site-wide denial of service condition. The KDC functionality remains unavailable until the server is restarted. In case of an attack where code injection and execution is successful, the behavior of the system is dependent on the intended purpose of the injected code. Any code injected into the vulnerable component would execute in the security context of the service process, which may be System or root level.

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 MIT Kerberos V5 KDC krb5_unparse_name Heap Overflow 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: Application Servers Protection Violation.
Attack Information: MIT Kerberos V5 KDC krb5_unparse_name heap overflow