A krb5 security update has been released for Fedora 33.

SECURITY: Fedora 33 Update: krb5-1.18.2-30.fc33

--------------------------------------------------------------------------------
Fedora Update Notification
FEDORA-2021-2bae525fd3
2021-07-21 01:14:27.761330
--------------------------------------------------------------------------------

Name : krb5
Product : Fedora 33
Version : 1.18.2
Release : 30.fc33
URL :   https://web.mit.edu/kerberos/www/
Summary : The Kerberos network authentication system
Description :
Kerberos V5 is a trusted-third-party network authentication system,
which can improve your network's security by eliminating the insecure
practice of sending passwords over the network in unencrypted form.

--------------------------------------------------------------------------------
Update Information:

- Fix KDC null deref on bad encrypted challenge - CVE-2021-36222 - Denial-
of-service only - (f34 only): pull-up to rawhide
--------------------------------------------------------------------------------
ChangeLog:

* Mon Jul 12 2021 Robbie Harwood - 1.18.2-30
- Fix KDC null deref on bad encrypted challenge (CVE-2021-36222)
--------------------------------------------------------------------------------

This update can be installed with the "dnf" update program. Use
su -c 'dnf upgrade --advisory FEDORA-2021-2bae525fd3' at the command
line. For more information, refer to the dnf documentation available at
  http://dnf.readthedocs.io/en/latest/command_ref.html#upgrade-command-label

All packages are signed with the Fedora Project GPG key. More details on the
GPG keys used by the Fedora Project can be found at
  https://fedoraproject.org/keys