A  variant uses a C2 mechanism similar to port knocking that allows attackers to connect to a victim without leaving the connection open for more than a few sectonds.
Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request. ### Instruction: List the MITRE techniques contained in the text. ### Input: A  variant uses a C2 mechanism similar to port knocking that allows attackers to connect to a victim without leaving the connection open for more than a few sectonds. ### Response: T1094.