Host Files System Changes via Windows Subsystem for Linux

Last updated 5 months ago on 2025-03-20
Created 3 years ago on 2023-01-12

About

Detects files creation and modification on the host system from the 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: 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
winlogbeat-*logs-endpoint.events.process-*logs-endpoint.events.file-*logs-windows.sysmon_operational-*
Related Integrations

endpoint(opens in a new tab or window)

windows(opens in a new tab or window)

Query
sequence by process.entity_id with maxspan=5m
 [process where host.os.type == "windows" and event.type == "start" and
  process.name : "dllhost.exe" and
   /* Plan9FileSystem CLSID - WSL Host File System Worker */
  process.command_line : "*{DFB65C4C-B34F-435D-AFE9-A86218684AA8}*"]
 [file where host.os.type == "windows" and process.name : "dllhost.exe" and not file.path : "?:\\Users\\*\\Downloads\\*"]

Install detection rules in Elastic Security

Detect Host Files System Changes 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).