Symmetric Cryptography
Where this stands
No Sigma rule can address this — the telemetry MITRE names has no Sigma logsource behind it.
Sigma has no logsource taxonomy for mobile platforms. MITRE's telemetry here is mobile EDR and device APIs, which no Sigma rule can address.
What the technique is
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. Symmetric encryption algorithms use the same key for plaintext encryption and ciphertext decryption. Common symmetric encryption algorithms include AES, Blowfish, and RC4.
Read it on attack.mitre.orgWhat MITRE says you would watch
- AN1731
An application performs repeated symmetric cryptographic operations (e.g., AES/RC4) on collected or staged data using locally accessible or reusable keys, followed by structured outbound communication. Detection correlates symmetric crypto API invocation + key reuse patterns + data staging + background execution context + network transmission, especially when inconsistent with expected application functionality.
- AN1732
Indirect evidence of symmetric cryptographic channel usage inferred through repeated structured encrypted network transmissions and background processing patterns, where direct observation of symmetric crypto operations is limited. Detection correlates application background execution + consistent encrypted payload patterns + app entitlement posture to identify misuse of symmetric encryption for command and control.
Technique names and descriptions © MITRE ATT&CK®, CC BY 4.0. Not endorsed by MITRE.