Check Point Advisories

MailEnable SMTP NTLM Authentication Buffer Overflow

Vulnerability
Protection

Check Point Reference:	CPAI-2006-304
Date Published:	19 Sep 2010
Severity:	High
Last Updated:	Sunday 14 February, 2016
Source:
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?
Vulnerability Description	A buffer overflow vulnerability exists in MailEnable server products. The flaw is caused by insufficient validation checks when processing the signature field of NTLM Type1 messages within the SMTP service. A remote unauthenticated attacker may successfully exploit this vulnerability to execute arbitrary code on the vulnerable machine. In an attack case where code injection is not successful, the affected SMTP service will terminate upon processing of the malicious message. If the SMTP service is not configured to restart automatically, the services will be unavailable until the process is restarted manually. In a more sophisticated attack, where code injection is successful, the behavior of the target host is entirely dependent on the intended function of the injected code. The code in such a case would execute within the security context of the SYSTEM account.

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 MailEnable SMTP NTLM Authentication Buffer 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: SMTP Protection Violation.
Attack Information: MailEnable SMTP NTLM authentication buffer overflow