kdc/do_tgs_req.c in MIT Kerberos 5 (aka krb5) 1.21 before 1.21.2 has a double free that is reachable if an authenticated user can trigger an authorization-data handling failure. Incorrect data is copied from one ticket to another. https://github.com/krb5/krb5/commit/88a1701b423c13991a8064feeb26952d3641d840 https://web.mit.edu/kerberos/www/advisories/ https://github.com/krb5/krb5/compare/krb5-1.21.1-final...krb5-1.21.2-final
This issue has been addressed in the following products: Red Hat Enterprise Linux 9 Via RHSA-2023:6699 https://access.redhat.com/errata/RHSA-2023:6699