'ssh in OpenSSH before 4.7 does not properly handle when an untrusted cookie cannot be created and uses a trusted X11 cookie instead, which allows attackers to violate intended policy and gain privileges by causing an X client to be treated as trusted.'
This issue was resolved in a backported fix. Current up to date versions not affected.
This issue was resolved in openssh-4.3p2-26.el5_2.1. Current versions meet or exceed this minor release.
To validate that you are running openssh-4.3p2-26.el5_2.1 or later, run the following:
rpm -qi openssh
If you need to update, run the following:
yum update