Updated krb5 packages that correct a security flaw are now available for
Red Hat Enterprise Linux 5.
This update has been rated as having important security impact by the Red
Hat Security Response Team.
Kerberos is a network authentication system which allows clients and
servers to authenticate to each other through use of symmetric encryption
and a trusted third party, the KDC. kadmind is the KADM5 administration
The MIT Kerberos Team discovered a problem with the originally published
patch for svc_auth_gss.c (CVE-2007-3999). A remote unauthenticated
attacker who can access kadmind could trigger this flaw and cause kadmind
to crash. On Red Hat Enterprise Linux 5 it is not possible to exploit this
flaw to run arbitrary code as the overflow is blocked by FORTIFY_SOURCE.
This issue did not affect the versions of Kerberos distributed with Red
Hat Enterprise Linux 2.1, 3, or 4.
Users of krb5-server are advised to update to these erratum packages which
contain a corrected backported fix for this issue.