Final answer:
A SYN flood that is altered to spoof both source and destination addresses as a single victim IP is called a Land Attack. It is a type of Denial of Service (DoS) attack aiming to exhaust the victim server's resources by having it reply to itself.
Step-by-step explanation:
When a SYN flood is altered so that the SYN packets are spoofed to have the same source and destination addresses, essentially defining both as a single victim IP address, this type of attack is referred to as a Land Attack. This is a kind of Denial of Service (DoS) attack, where the purpose is to exhaust the resources of the victim system to make it unresponsive. The Land Attack operates by causing the victim server to reply to itself, continuously tying up its resources and eventually causing a crash.
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