A security analyst is investigating a potential network-level session hijacking incident.

The attacker has most likely used RST hijacking, which is a type of network-level session hijacking technique that exploits the TCP reset (RST) mechanism. TCP reset is a way of terminating an established TCP connection by sending a packet with the RST flag set, indicating that the sender does not want to continue the communication. RST hijacking involves sending a forged RST packet to one or both ends of a TCP connection, using a spoofed source IP address and a guessed acknowledgment number, to trick them into believing that the other end has closed the connection. As a result, the victim’s connection is reset and the attacker can take over the session or launch a denial-of-service attack12.

The other options are not correct for the following reasons:

A. TCP/IP hijacking: This option is a general term that refers to any type of network-level session hijacking technique that targets TCP/IP connections. RST hijacking is a specific type of TCP/IP hijacking, but not the only one. Other types of TCP/IP hijacking include SYN hijacking, source routing, and sequence prediction3.

B. UDP hijacking: This option is not applicable because UDP is a connectionless protocol that does not use TCP reset mechanism. UDP hijacking is a type of network-level session hijacking technique that targets UDP connections, such as DNS or VoIP. UDP hijacking involves intercepting and modifying UDP packets to redirect or manipulate the communication between the sender and the receiver4.

D. Blind hijacking: This option is not accurate because blind hijacking is a type of network-level session hijacking technique that does not require injecting RST packets. Blind hijacking involves guessing the sequence and acknowledgment numbers of a TCP connection without being able to see the responses from the target. Blind hijacking can be used to inject malicious data or commands into an active TCP session, but not to reset the connection5.