Updated Kerberos 5 packages are now available for CentOS LInux Advanced Server. These updates fix a buffer overflow in the XDR decoder.
Sun RPC is a remote procedure call framework which allows clients to invoke procedures in a server process over a network. XDR is a mechanism for encoding data structures for use with RPC. The Kerberos 5 network authentication system contains an RPC library which includes an XDR decoder derived from Sun's RPC implementation. The Sun implementation was recently demonstrated to be vulnerable to a heap overflow. It is believed that the attacker needs to be able to authenticate to the kadmin daemon for this attack to be successful. No exploits are known to currently exist. All users should upgrade to these errata packages which contain an updated version of Kerberos 5 which is not vulnerable to this issue.