Description
Adversaries may communicate using a protocol and port pairing that are typically not associated. For example, HTTPS over port 8088(Citation: Symantec Elfin Mar 2019) or port 587(Citation: Fortinet Agent Tesla April 2018) 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.(Citation: change_rdp_port_conti)
Threat-Mapped Scoring
Threat Score:
0.0
Industry:
Threat Priority:
Unclassified
ATT&CK Kill Chain Metadata
- Tactics: command-and-control
- Platforms: Linux, macOS, Windows, ESXi
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Detection Guidance:
Analyze packet contents to detect communications that do not follow the expected protocol behavior for the port that is being used. Analyze network data for uncommon data flows (e.g., a client sending significantly more data than it receives from a server). Processes utilizing the network that do not normally have network communication or have never been seen before are suspicious.(Citation: University of Birmingham C2)