Port scanning is some dark stuff when the whole aim of using it is to satisfy a selfish desire. Don’t be a Lord Voldemort to try it. Just know what it is, do not use it for personal or selfish reasons !!
Well, network administrators may use it for verification of security policies of their networks, while the Voldemort kind of guy would only want to accomplish his selfish aims with it.
- It is a series of messages sent by someone attempting to break into a computer to learn lots of stuff associated with a "well-known" port number especially its weaknesses. The feat is achieved by sending a message to each port and then getting a response which would indicate if the port is used and then , exploit it.
It can lead to a denial of service (DoS) attack. That happens when you continuously go into a target using portscans
I wont be saying much about this.
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