Red Hat today issued software updates to fix at least 5-6 security vulnerabilities in various versions of its Linux distribution. These update has been rated as having important security impact. It is recommended that you upgrade (patch) your system using yum command.

A flaw was found in Perl’s regular expression engine. A specially crafted regular expression with Unicode characters could trigger a buffer overflow, causing Perl to crash, or possibly execute arbitrary code with the privileges of the user running Perl.

An input validation flaw was discovered in X.org’s Security and Record extensions. A malicious authorized client could exploit this issue to cause a denial of service (crash) or, potentially, execute arbitrary code with root privileges on the X.Org server.

How do I patch my RHEL system?

Simply, type the following command:
# yum update

How do I patch my Debian Linux system?

Debian also updated many of its package to address these vulnerabilities in the X Window system. You can upgrade your system by typing following commands:
# apt-get update
# apt-get upgrade

I’m sure other distros will also release updates.