(RHSA-2004:448) krb5 security update

Kerberos is a networked authentication system that uses a trusted third
party (a KDC) to authenticate clients and servers to each other.

Several double-free bugs were found in the Kerberos 5 KDC and libraries. A
remote attacker could potentially exploit these flaws to execuate arbitrary
code. The Common Vulnerabilities and Exposures project (cve.mitre.org) has
assigned the names CAN-2004-0642 and CAN-2004-0643 to these issues.

A double-free bug was also found in the krb524 server (CAN-2004-0772),
however this issue was fixed for Red Hat Enterprise Linux 2.1 users by a
previous erratum, RHSA-2003:052.

An infinite loop bug was found in the Kerberos 5 ASN.1 decoder library. A
remote attacker may be able to trigger this flaw and cause a denial of
service. The Common Vulnerabilities and Exposures project (cve.mitre.org)
has assigned the name CAN-2004-0644 to this issue.

All users of krb5 should upgrade to these updated packages, which contain
backported security patches to resolve these issues.