Elastic Security Detection Rules

Linux SSH X11 Forwarding

Last updated 14 days ago on 2025-01-17
Created a year ago on 2023-08-23

About

This rule monitors for X11 forwarding via SSH. X11 forwarding is a feature that allows users to run graphical applications on a remote server and display the application's graphical user interface on their local machine. Attackers can abuse X11 forwarding for tunneling their GUI-based tools, pivot through compromised systems, and create covert communication channels, enabling lateral movement and facilitating remote control of systems within a network.
Tags
Domain: EndpointOS: LinuxUse Case: Threat DetectionTactic: Command and ControlData Source: Elastic DefendData Source: Elastic EndgameData Source: CrowdstrikeData Source: SentinelOneLanguage: eql
Severity
low
Risk Score
21
MITRE ATT&CK™

Command and Control (TA0011)(opens in a new tab or window)

↳ Protocol Tunneling (T1572)(opens in a new tab or window)

License
Elastic License v2(opens in a new tab or window)

Definition

Rule Type
Event Correlation Rule
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
logs-endpoint.events.*endgame-*logs-crowdstrike.fdr*logs-sentinel_one_cloud_funnel.*
Related Integrations

endpoint(opens in a new tab or window)

crowdstrike(opens in a new tab or window)

sentinel_one_cloud_funnel(opens in a new tab or window)

Query
process where host.os.type == "linux" and event.type == "start" and event.action in ("exec", "exec_event", "start", "ProcessRollup2") and
process.name in ("ssh", "sshd") and process.args in ("-X", "-Y") and process.args_count >= 3 and
process.parent.name in ("bash", "dash", "ash", "sh", "tcsh", "csh", "zsh", "ksh", "fish")

Install detection rules in Elastic Security

Detect Linux SSH X11 Forwarding in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(opens in a new tab or window).