ec_verify in kdc/kdc_preauth_ec.c in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) before 1.18.4 and 1.19.x before 1.19.2 allows remote attackers to cause a NULL pointer dereference and daemon crash. This occurs because a return value is not properly managed in a certain situation.
https://www.oracle.com/security-alerts/cpuoct2021.html
https://www.debian.org/security/2021/dsa-4944
https://web.mit.edu/kerberos/advisories/
https://security.netapp.com/advisory/ntap-20211104-0007/
https://security.netapp.com/advisory/ntap-20211022-0003/
https://github.com/krb5/krb5/releases
https://github.com/krb5/krb5/commit/fc98f520caefff2e5ee9a0026fdf5109944b3562