Check Point Advisories

Cesanta Mongoose DNS Compressed Name Denial of Service (CVE-2017-2909)

Vulnerability
Protection

Check Point Reference:	CPAI-2017-1001
Date Published:	16 Nov 2017
Severity:	Medium
Last Updated:	Monday 27 November, 2017
Source:	Cesanta
Industry Reference:	CVE-2017-2909
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?	Cesanta Mongoose 6.8 and prior
Vulnerability Description	An infinite loop vulnerability exists in the DNS server functionality of Cesanta Mongoose. The vulnerability is due to insufficient handling of compressed names in DNS queries and responses. A remote, unauthenticated attacker can exploit this vulnerability by sending a crafted DNS query or response to an application implementing the Mongoose DNS server functionality or DNS client functionality, respectively.

Protection Overview

This protection detects 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 Cesanta Mongoose DNS Compressed Name 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: DNS Enforcement Violation.
Attack Information: Cesanta Mongoose DNS Compressed Name Denial of Service