Which TCP flag can be the default response to a probe on a closed port?
A) RST
B) URG
C) PSH
D) SYN

Question

Quizplus · Accepted Answer

When a probe is sent to a closed port, the default response from the host is to send a TCP segment with the Reset (RST) flag set. This indicates to the sender that the port is closed and there is no active service running on it. Other TCP flags like URG, PSH, and SYN are not relevant in this context.

Which TCP Flag Can Be the Default Response to a Probe