[ GLSA 200809-09 ] Postfix: Denial of Service

[GLSA]

Gentoo Linux Security Advisory

Title: Postfix: Denial of Service (GLSA 200809-09)
Severity: normal
Exploitable: local
Date: September 19, 2008
Bug(s): #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: mail-mta/postfix
Vulnerable: < 2.4.9
Vulnerable: < 2.5.5
Unaffected: >= 2.4.9
Unaffected: >= 2.5.5
Architectures: 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: