Information Assurance

Information Assurance

Bugtraq Analysis

back to bugtraq analyses page

Bugtraq: GNU Mailman Vulnerability
Published: March 29, 2006 12:00AM
Link: http://www.securityfocus.com/bid/17311

There is a vulnerability in GNU Mailman (a popular free program that controls mailing lists on many, many servers). Essentially, a malformed MIME message can cause a Denial of Service attack on Mailman and temporarily shut it down. Specifically, it fails in parsing the message (input validation error) when using the attachment scrubber utility. It can be triggered by a mailing list post from a remote user and cause the application to become inoperative. This affects Linux and Unix operating systems that have web servers using Mailman.

Better exception handling as well as filters set by the mail list admin could help prevent this problem. A listserv administrator can establish protections based on the type of email. This will help prevent malformed non-text emails from successfully going through the server. Ultimately, a patch, which has already been released, prevents this problem completely.

As a temporary workaround, if a user finds their Mailman application freezing up frequently, they can just reset the program in order to get it running again. However, this doesn't really address the problem, it only deals with the consequences of a denail of service attack.

To prevent this problem from occuring in the future, server administrators should make sure to install the recently released patch.