The kg_accept_krb5 function in krb5/accept_sec_context.c in the GSS-API library in MIT Kerberos 5 (aka krb5) through 1.7.1 and 1.8 before 1.8.2, as used in kadmind and other applications, does not properly check for invalid GSS-API tokens, which allows remote authenticated users to cause a denial of service (NULL pointer dereference and daemon crash) via an AP-REQ message in which the authenticator's checksum field is missing. Per: http://web.mit.edu/kerberos/advisories/MITKRB5-SA-2010-005.txt
kadmind and other GSS-API server applications in all known releases of MIT krb5, up to and including krb5-1.8.1
third-party GSS-API server applications that link link against the GSS-API library in all known releases of MIT krb5, up to and including krb5-1.8.1
Independent implementations of the krb5 GSS-API mechanism may be vulnerable, as the underlying bug is based on plausible (but invalid) assumptions about the Kerberos protocol.' Per: http://cwe.mitre.org/data/definitions/476.html
'CWE-476: NULL Pointer Dereference'