December 28, 2011 8:30 AM ET
Redhat krb5 Critical Security Update
RHEL Desktop Workstation (v. 5 client)
Vulnerability can be exploited by malicious people to compromise a vulnerable system.
krb5 telnet daemon is not enabled by default in any version of Red Hat Enterprise Linux. In addition, the default firewall rules block remote access to the telnet port. This flaw does not affect the telnet daemon distributed in the telnet-server package.
For users who have installed the krb5-workstation package, have enabled the telnet daemon, and have it accessible remotely, this update should be applied immediately.
All krb5-workstation users should upgrade to these updated packages, which contain a backported patch to correct this issue.
A buffer overflow flaw was found in the MIT krb5 telnet daemon (telnetd) as shipped with all supported versions of Red Hat Enterprise Linux. A remote attacker who can access the telnet port of a target machine could use this flaw to execute arbitrary code as root.
Red Hat is working on an updated packages to address this flaw. For users who have enabled the krb5 telnet daemon and have it accessible remotely, they should disable it until Red Hat provide updated packages to correct this flaw. Red Hat Support
Update Red Hat or apply patch. Red Hat Security Patches
Update to krb5 version 1.8. Apply patch for krb5-appl. Kerberos Releases