CVE-2018-16841

Samba from version 4.3.0 and before versions 4.7.12, 4.8.7 and 4.9.3 are
vulnerable to a denial of service. When configured to accept smart-card
authentication, Samba’s KDC will call talloc_free() twice on the same
memory if the principal in a validly signed certificate does not match the
principal in the AS-REQ. This is only possible after authentication with a
trusted certificate. talloc is robust against further corruption from a
double-free with talloc_free() and directly calls abort(), terminating the
KDC process.

Bugs

• <https://bugzilla.samba.org/show_bug.cgi?id=13628&gt;