The following updates have been uploaded to the mirror for CentOS-2 RHSA-2004:172 Updated mc packages resolve several vulnerabilities RHSA-2004:180 Updated libpng packages fix crash RHSA-2004:190 Updated cvs package fixes security issue RHSA-2004:191 Updated cadaver package fixes security vulnerability in neon RHSA-2004:192 Updated rsync package fixes security issue
See the rh errara for details. https://rhn.redhat.com/errata/rh21as-errata.html
To update your machine just run # yum update
John.