GLSA 200809-09: Postfix: Denial of Service

Severity:normal
Title:Postfix: Denial of Service
Date:09/19/2008
Bugs: #236453
ID:200809-09

Synopsis

A memory leak in Postfix might allow local users to cause a Denial of Service.

Background

Postfix is Wietse Venema's mailer that attempts to be fast, easy to administer, and secure, as an alternative to the widely-used Sendmail program.

Affected packages

Package Vulnerable Unaffected Architecture(s)
mail-mta/postfix < 2.4.9 >= 2.4.9 All supported architectures

Description

It has been discovered than Postfix leaks an epoll file descriptor when executing external commands, e.g. user-controlled $HOME/.forward or $HOME/.procmailrc files. NOTE: This vulnerability only concerns Postfix instances running on Linux 2.6 kernels.

Impact

A local attacker could exploit this vulnerability to reduce the performance of Postfix, and possibly trigger an assertion, resulting in a Denial of Service.

Workaround

Allow only trusted users to control delivery to non-Postfix commands.

Resolution

All Postfix 2.4 users should upgrade to the latest version:

    # emerge --sync
    # emerge --ask --oneshot --verbose ">=mail-mta/postfix-2.4.9"

All Postfix 2.5 users should upgrade to the latest version:

# emerge --sync # emerge --ask --oneshot --verbose ">=mail-mta/postfix-2.5.5"

References

Availability

This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-200809-09.xml

Concerns?

Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users machines is of utmost importance to us. Any security concerns should be addressed to security@gentoo.org or alternatively, you may file a bug at https://bugs.gentoo.org.

License

Copyright 2010 Gentoo Foundation, Inc; referenced text belongs to its owner(s). The contents of this document are licensed under the Creative Commons - Attribution / Share Alike license.

Thank you!