Execution via Windows Subsystem for Linux

Last updated 10 days ago on 2025-02-21
Created 2 years ago on 2023-01-12

About

Detects attempts to execute a program on the host from the Windows Subsystem for Linux. Adversaries may enable and use WSL for Linux to avoid detection.
Tags
Domain: EndpointOS: WindowsUse Case: Threat DetectionTactic: Defense EvasionData Source: Elastic EndgameData Source: Elastic DefendData Source: Windows Security Event LogsData Source: Microsoft Defender for EndpointData Source: SentinelOneData Source: CrowdstrikeData Source: SysmonLanguage: eql
Severity
medium
Risk Score
47
MITRE ATT&CK™

Defense Evasion (TA0005)(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
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-*
Related Integrations

endpoint(opens in a new tab or window)

windows(opens in a new tab or window)

system(opens in a new tab or window)

m365_defender(opens in a new tab or window)

sentinel_one_cloud_funnel(opens in a new tab or window)

crowdstrike(opens in a new tab or window)

Query
process where host.os.type == "windows" and event.type : "start" and
  process.parent.name : ("wsl.exe", "wslhost.exe") and
  not process.executable : (
        "?:\\Program Files (x86)\\*",
        "?:\\Program Files\\*",
        "?:\\Program Files*\\WindowsApps\\MicrosoftCorporationII.WindowsSubsystemForLinux_*\\wsl*.exe",
        "?:\\Windows\\System32\\conhost.exe",
        "?:\\Windows\\System32\\lxss\\wslhost.exe",
        "?:\\Windows\\System32\\WerFault.exe",
        "?:\\Windows\\Sys?????\\wslconfig.exe"
  ) and
  not (
    event.dataset == "crowdstrike.fdr" and
      process.executable : (
        "\\Device\\HarddiskVolume?\\Program Files (x86)\\*",
        "\\Device\\HarddiskVolume?\\Program Files\\*",
        "\\Device\\HarddiskVolume?\\Program Files*\\WindowsApps\\MicrosoftCorporationII.WindowsSubsystemForLinux_*\\wsl*.exe",
        "\\Device\\HarddiskVolume?\\Windows\\System32\\conhost.exe",
        "\\Device\\HarddiskVolume?\\Windows\\System32\\lxss\\wslhost.exe",
        "\\Device\\HarddiskVolume?\\Windows\\System32\\WerFault.exe",
        "\\Device\\HarddiskVolume?\\Windows\\Sys?????\\wslconfig.exe"
      )
  )

Install detection rules in Elastic Security

Detect Execution via Windows Subsystem for Linux 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).