The kdc_handle_protected_negotiation function in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) 1.8.x, 1.9.x before 1.9.5, and 1.10.x before 1.10.3 attempts to calculate a checksum before verifying that the key type is appropriate for a checksum, which allows remote attackers to execute arbitrary code or cause a denial of service (uninitialized pointer free, heap memory corruption, and daemon crash) via a crafted AS-REQ request.
server/server_stubs.c in the kadmin protocol implementation in MIT Kerberos 5 (aka krb5) 1.10 before 1.10.1 does not properly restrict access to (1) SET_STRING and (2) GET_STRINGS operations, which might allow remote authenticated administrators to modify or read string attributes by leveraging the global list privilege.
The check_1_6_dummy function in lib/kadm5/srv/svr_principal.c in kadmind in MIT Kerberos 5 (aka krb5) 1.8.x, 1.9.x, and 1.10.x before 1.10.2 allows remote authenticated administrators to cause a denial of service (NULL pointer dereference and daemon crash) via a KRB5_KDB_DISALLOW_ALL_TIX create request that lacks a password.