Samba client code always requests a forwardable ticket when using Kerberos authentication. This means the target server, which must be in the current or trusted domain/realm, is given a valid general purpose Kerberos "Ticket Granting Ticket" (TGT), which can be used to fully impersonate the authenticated user or service. https://nvd.nist.gov/vuln/detail/CVE-2016-2125
