An integer overflow bug has been discovered in the RPC library used by the Kerberos 5 administration system, which is derived from the SunRPC library. This bug could be exploited to gain unauthorized root access to a KDC host. 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 exist yet.
This problem has been fixed in version 1.2.4-5woody1 for the current stable distribution (woody) and in version 1.2.5-2 for the unstable distribution (sid). Debian 2.2 (potato) is not affected since it doesn't contain krb5 packages.
We recommend that you upgrade your kerberos packages immediately.