Skip to content
Every technique
T1571Detection written

Non-Standard Port

Command and ControlESXi, Linux, macOS, Windows

Where this stands

One published detection covers this technique. Every one is unverified — no rule on Siemphony has been executed against real telemetry.

What the technique is

Adversaries may communicate using a protocol and port pairing that are typically not associated. For example, HTTPS over port 8088 or port 587 as opposed to the traditional port 443. Adversaries may make changes to the standard port used by a protocol to bypass filtering or muddle analysis/parsing of network data. Adversaries may also make changes to victim systems to abuse non-standard ports. For example, Registry keys and other configuration settings can be used to modify protocol and port pairings.

Read it on attack.mitre.org

What MITRE says you would watch

  • AN0633

    Processes initiating outbound connections on uncommon ports or using protocols inconsistent with the assigned port. Correlating process creation with subsequent network connections reveals anomalies such as svchost.exe or Office applications using high, atypical ports.

  • AN0634

    Unusual daemons or user processes binding/listening on ports outside of standard ranges, or initiating client connections using mismatched protocol/port pairings.

  • AN0635

    Applications making outbound connections on non-standard ports or launchd services bound to ports inconsistent with system baselines.

Technique names and descriptions © MITRE ATT&CK®, CC BY 4.0. Not endorsed by MITRE.