Check Point Advisories

OpenLDAP LDAP Server BIND Request Denial of Service

Vulnerability
Protection

Check Point Reference:	CPAI-2006-273
Date Published:	13 Jun 2010
Severity:	High
Last Updated:	Sunday 29 April, 2018
Source:
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?
Vulnerability Description	OpenLDAP is an open-source implementation of the Lightweight Directory Access Protocol (LDAP) service. On a default installation, the OpenLDAP server uses TCP port 389 for communication. There exists a vulnerability in the OpenLDAP Lightweight Directory Access Protocol (LDAP) service. The flaw is due to an improper handling of specially crafted BIND requests sent to the server which contain overly long CRAM-MD5 credential strings. This can be exploited by an unauthenticated remote attacker to cause an assertion failure, and thus, causing a Denial of Service condition in the affected service. The target server process will terminate as a result of an attack. Consequently, all established connections will be severed and further connections will not be possible until the server is manually restarted.

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 OpenLDAP LDAP Server BIND Request 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: LDAP Protection Violation.
Attack Information: OpenLDAP LDAP server BIND request denial of service