exim security update

Updated exim packages that fix a security issue in PCRE and a free space
computation on large file system bug are now available for Red Hat
Enterprise Linux 4.

This update has been rated as having moderate security impact by the Red
Hat Security Response Team.

Exim is a mail transport agent (MTA) developed at the University of
Cambridge for use on Unix systems connected to the Internet.

An integer overflow flaw was found in PCRE, a Perl-compatible regular
expression library included within Exim. A local user could create a
maliciously crafted regular expression in such as way that they could gain
the privileges of the 'exim' user. The Common Vulnerabilities and
Exposures project assigned the name CAN-2005-2491 to this issue. These
erratum packages change Exim to use the system PCRE library instead of the
internal one.

These packages also fix a minor flaw where the Exim Monitor was incorrectly
computing free space on very large file systems.

Users should upgrade to these erratum packages and also ensure they have
updated the system PCRE library, for which erratum packages are available
seperately in RHSA-2005:761

Before applying this update, make sure that all previously-released
errata relevant to your system have been applied. Use Red Hat
Network to download and update your packages. To launch the Red Hat
Update Agent, use the following command:

up2date

For information on how to install packages manually, refer to the
following Web page for the System Administration or Customization
guide specific to your system:

http://www.redhat.com/docs/manuals/enterprise/

166332 - CAN-2005-2491 PCRE heap overflow

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2005-2491