Updated krb5 packages are now available for CentOS Linux 4 to
correct a privilege escalation security flaw.
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.
A flaw was found where some bundled Kerberos-aware applications would fail
to check the result of the setuid() call. On Linux 2.6 kernels, the
setuid() call can fail if certain user limits are hit. A local attacker
could manipulate their environment in such a way to get the applications to
continue to run as root, potentially leading to an escalation of
Users are advised to update to these erratum packages which contain a
backported fix to correct this issue.