TA0011 · COMMAND AND CONTROL
Symmetric Cryptography
Adversaries may employ a known symmetric encryption algorithm to conceal command and control traffic rather than relying on any inherent protections provided by a communication protocol.
Detect it with
With symmetric encryption, it may be possible to obtain the algorithm and key from samples and use them to decode network traffic to detect malware communications signatures.
Why it matters on shift
Symmetric Cryptography is one of the concrete ways adversaries achieve command and control. Recognising it in telemetry lets you name the technique in your ticket and pivot to what came before and after.
What to look for next
After command and control, the next tactic is usually Exfiltration. Search your telemetry for the transition before closing the ticket.
Kill-chain context