In MIT Kerberos 5 (aka krb5) 1.7 and later, an authenticated attacker can cause a KDC assertion failure by sending invalid S4U2Self or S4U2Proxy requests.
The validate_as_request function in kdc_util.c in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) before 1.13.6 and 1.4.x before 1.14.3, when restrict_anonymous_to_tgt is enabled, uses an incorrect client data structure, which allows remote authenticated users to cause a denial of service (NULL pointer dereference and daemon crash) via an S4U2Self request.
The process_db_args function in plugins/kdb/ldap/libkdb_ldap/ldap_principal2.c in the LDAP KDB module in kadmind in MIT Kerberos 5 (aka krb5) through 1.13.4 and 1.14.x through 1.14.1 mishandles the DB argument, which allows remote authenticated users to cause a denial of service (NULL pointer dereference and daemon crash) via a crafted request to modify a principal.
Multiple memory leaks in kadmin/server/server_stubs.c in kadmind in MIT Kerberos 5 (aka krb5) before 1.13.4 and 1.14.x before 1.14.1 allow remote authenticated users to cause a denial of service (memory consumption) via a request specifying a NULL principal name.
The (1) kadm5_create_principal_3 and (2) kadm5_modify_principal functions in lib/kadm5/srv/svr_principal.c in kadmind in MIT Kerberos 5 (aka krb5) 1.12.x and 1.13.x before 1.13.4 and 1.14.x before 1.14.1 allow remote authenticated users to cause a denial of service (NULL pointer dereference and daemon crash) by specifying KADM5_POLICY with a NULL policy name.
The xdr_nullstring function in lib/kadm5/kadm_rpc_xdr.c in kadmind in MIT Kerberos 5 (aka krb5) before 1.13.4 and 1.14.x before 1.14.1 does not verify whether '\0' characters exist as expected, which allows remote authenticated users to obtain sensitive information or cause a denial of service (out-of-bounds read) via a crafted string.
The iakerb_gss_export_sec_context function in lib/gssapi/krb5/iakerb.c in MIT Kerberos 5 (aka krb5) 1.14 pre-release 2015-09-14 improperly accesses a certain pointer, which allows remote authenticated users to cause a denial of service (memory corruption) or possibly have unspecified other impact by interacting with an application that calls the gss_export_sec_context function. NOTE: this vulnerability exists because of an incorrect fix for CVE-2015-2696.