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MITRE ATT&CK sub-technique

T1205.001 — Port Knocking

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T1205.001 (Port Knocking) is a MITRE ATT&CK sub-technique tracked in WhisperGraph, serving the Stealth, Persistence, Command and Control tactics.

Description

Adversaries may use port knocking to hide open ports used for persistence or command and control. To enable a port, an adversary sends a series of attempted connections to a predefined sequence of closed ports. After the sequence is completed, opening a port is often accomplished by the host based firewall, but could also be implemented by custom software. This technique has been observed both for the dynamic opening of a listening port as well as the initiating of a connection to a listening server on a different system. The observation of the signal packets to trigger the communication can be conducted through different methods. One means, originally implemented by Cd00r (Citation: Hartrell cd00r 2002), is to use the libpcap libraries to sniff for the packets in question. Another method leverages raw sockets, which enables the malware to use ports that are already open for use by other programs.

Tactics

Related techniques

Parent technique: T1205 · Traffic Signaling

Threat actors observed using this technique

© The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation.

Related pages

Pivot from T1205.001 into its tactic, related techniques and the actors that use it.

Queries

Resolves the segment to this technique or tactic.


MATCH (t:ATTACK_PATTERN {name: $id})
RETURN t.id AS id, t.name AS name, t.kind AS kind, t.description AS description
Run yourself →

The tactic(s) this technique serves.


MATCH (t:ATTACK_PATTERN {name: $id})-[:USES_TACTIC]->(tac:ATTACK_PATTERN)
RETURN tac.id AS id, tac.name AS name
LIMIT 10
Run yourself →

This id's parent technique, if it is a sub-technique.


MATCH (p:ATTACK_PATTERN {name: $parentId})
RETURN p.id AS id, p.name AS name
LIMIT 1
Run yourself →

Sub-techniques of this technique, if any.


MATCH (c:ATTACK_PATTERN) WHERE c.id STARTS WITH $subPrefix
RETURN c.id AS id, c.name AS name
ORDER BY c.id
LIMIT 25
Run yourself →

Threat actors observed using this technique.


MATCH (a:ACTOR)-[:USES_TECHNIQUE]->(t:ATTACK_PATTERN {name: $id})
RETURN a.name AS name
LIMIT 100
Run yourself →

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