Execution via GitHub Actions Runner

[metadata]
creation_date = "2025/11/26"
integration = ["endpoint", "windows", "system", "m365_defender", "sentinel_one_cloud_funnel", "crowdstrike", "auditd_manager"]
maturity = "production"
updated_date = "2026/03/24"

[rule]
author = ["Elastic"]
description = """
This rule detects potentially dangerous commands spawned by the GitHub Actions Runner.Worker process on self-hosted runner
machines. Adversaries who gain the ability to modify or trigger workflows in a linked GitHub repository can execute
arbitrary commands on the runner host. This behavior may indicate malicious or unexpected workflow activity, including
code execution, file manipulation, or network exfiltration initiated through a compromised repository or unauthorized
workflow.
"""
false_positives = [
    "Authorized GitHub actions runner with no malicious workflow actions.",
]
from = "now-9m"
index = [
    "endgame-*",
    "logs-crowdstrike.fdr*",
    "logs-endpoint.events.process-*",
    "logs-m365_defender.event-*",
    "logs-sentinel_one_cloud_funnel.*",
    "logs-system.security*",
    "logs-windows.forwarded*",
    "logs-windows.sysmon_operational-*",
    "winlogbeat-*",
    "auditbeat-*",
    "logs-auditd_manager.auditd-*"
]
language = "eql"
license = "Elastic License v2"
name = "Execution via GitHub Actions Runner"
note = """## Triage and analysis

### Investigating Execution via GitHub Actions Runner

Adversaries who gain the ability to modify or trigger workflows in a linked GitHub repository can execute arbitrary commands on the runner host.

### Possible investigation steps

- Review the execution details like process.command_line and if it's expected or not.
- Examine associated network and file activities and if there is any ingress tool transfer activity.
- Verify if there is adjascent any sensitive file access or collection.
- Correlate with other alerts and investiguate if this activity is related to a supply chain attack.

### False positive analysis

- Authorized github workflow actions.

### Response and remediation

- Immediately isolate the affected system from the network to prevent further unauthorized command execution and potential lateral movement.
- Terminate any suspicious child processes that were initiated by the Github actions runner.
- Conduct a thorough review of the affected system's logs and configurations to identify any unauthorized changes or additional indicators of compromise.
- Restore the system from a known good backup if any unauthorized changes or malicious activities are confirmed.
- Implement application whitelisting to prevent unauthorized execution.
- Escalate the incident to the security operations center (SOC) or incident response team for further investigation and to assess the potential impact on the broader network."""
references = [
    "https://www.elastic.co/blog/shai-hulud-worm-npm-supply-chain-compromise",
    "https://socket.dev/blog/shai-hulud-strikes-again-v2",
]
risk_score = 47
rule_id = "a640ef5b-e1da-4b17-8391-468fdbd1b517"
severity = "medium"
tags = [
    "Domain: Endpoint",
    "OS: Linux",
    "OS: Windows",
    "OS: macOS",
    "Use Case: Threat Detection",
    "Tactic: Execution",
    "Tactic: Initial Access",
    "Data Source: Elastic Endgame",
    "Data Source: Elastic Defend",
    "Data Source: Windows Security Event Logs",
    "Data Source: Microsoft Defender for Endpoint",
    "Data Source: Sysmon",
    "Data Source: SentinelOne",
    "Data Source: Crowdstrike",
    "Data Source: Auditd Manager",
    "Resources: Investigation Guide",
]
timestamp_override = "event.ingested"
type = "eql"

query = '''
process where event.type == "start" and event.action in ("exec", "exec_event", "start", "ProcessRollup2", "executed", "process_started") and
 process.parent.name in ("Runner.Worker", "Runner.Worker.exe") and
 (
   process.name like ("curl", "curl.exe", "wget", "wget.exe", "powershell.exe", "cmd.exe", "pwsh.exe", "certutil.exe", "rundll32.exe", "bash", "sh", "zsh", "tar", "rm",
                     "sed", "osascript", "chmod", "nohup", "setsid", "dash", "ash", "tcsh", "csh", "ksh", "fish", "python*", "perl*", "ruby*", "lua*", "php*", "node", "node.exe") or
   process.executable : ("/tmp/*", "/private/tmp/*", "/var/tmp/*", "/dev/shm/*", "/run/*", "/var/run/*", "?:\\Users\\*")
 )
'''


[[rule.threat]]
framework = "MITRE ATT&CK"

[[rule.threat.technique]]
id = "T1059"
name = "Command and Scripting Interpreter"
reference = "https://attack.mitre.org/techniques/T1059/"

[[rule.threat.technique.subtechnique]]
id = "T1059.001"
name = "PowerShell"
reference = "https://attack.mitre.org/techniques/T1059/001/"

[[rule.threat.technique.subtechnique]]
id = "T1059.002"
name = "AppleScript"
reference = "https://attack.mitre.org/techniques/T1059/002/"

[[rule.threat.technique.subtechnique]]
id = "T1059.003"
name = "Windows Command Shell"
reference = "https://attack.mitre.org/techniques/T1059/003/"

[[rule.threat.technique.subtechnique]]
id = "T1059.004"
name = "Unix Shell"
reference = "https://attack.mitre.org/techniques/T1059/004/"

[[rule.threat.technique.subtechnique]]
id = "T1059.006"
name = "Python"
reference = "https://attack.mitre.org/techniques/T1059/006/"

[[rule.threat.technique.subtechnique]]
id = "T1059.007"
name = "JavaScript"
reference = "https://attack.mitre.org/techniques/T1059/007/"

[rule.threat.tactic]
id = "TA0002"
name = "Execution"
reference = "https://attack.mitre.org/tactics/TA0002/"

[[rule.threat]]
framework = "MITRE ATT&CK"

[[rule.threat.technique]]
id = "T1195"
name = "Supply Chain Compromise"
reference = "https://attack.mitre.org/techniques/T1195/"

[[rule.threat.technique.subtechnique]]
id = "T1195.002"
name = "Compromise Software Supply Chain"
reference = "https://attack.mitre.org/techniques/T1195/002/"

[rule.threat.tactic]
id = "TA0001"
name = "Initial Access"
reference = "https://attack.mitre.org/tactics/TA0001/"

[[rule.threat]]
framework = "MITRE ATT&CK"

[[rule.threat.technique]]
id = "T1218"
name = "System Binary Proxy Execution"
reference = "https://attack.mitre.org/techniques/T1218/"

[[rule.threat.technique.subtechnique]]
id = "T1218.011"
name = "Rundll32"
reference = "https://attack.mitre.org/techniques/T1218/011/"

[rule.threat.tactic]
id = "TA0005"
name = "Defense Evasion"
reference = "https://attack.mitre.org/tactics/TA0005/"