Both the SYN and FIN control flags are not normally set in the
same TCP segment header. The SYN flag synchronizes sequence
numbers to initiate a TCP connection. The FIN flag indicates
the end of data transmission to finish a TCP connection. Their
purposes are mutually exclusive. A TCP header with the SYN and
FIN flags set is anomalous TCP behavior, causing various
responses from the recipient, depending on the OS.
When block both syn and fin option is enable, the device
drops the packet when it discovers such a header
This attribute records the TCP syn fin both set packet
dropped.