WSL Kali-Linux Usage

Status: experimental
Severity: high
Log source: category process_creation, product windows
Author: Swachchhanda Shrawan Poudel (Nextron Systems)
Source: github.com/SigmaHQ/sigma

Detects the use of Kali Linux through Windows Subsystem for Linux

Known false positives

Legitimate installation or usage of Kali Linux WSL by administrators or security teams

MITRE ATT&CK coverage

Tactic	Techniques
Stealth	`T1202` Indirect Command Execution

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation
Security-Auditing	Event ID 4688: A new process has been created.

Rule body

title: WSL Kali-Linux Usage
id: 6f1a11aa-4b8a-4b7f-9e13-4d3e4ff0e0d4
status: experimental
description: Detects the use of Kali Linux through Windows Subsystem for Linux
references:
    - https://medium.com/@redfanatic7/running-kali-linux-on-windows-51ad95166e6e
    - https://learn.microsoft.com/en-us/windows/wsl/install
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-10-10
tags:
    - attack.stealth
    - attack.t1202
logsource:
    category: process_creation
    product: windows
detection:
    selection_img_appdata:
        - Image|contains|all:
              - ':\Users\'
              - '\AppData\Local\packages\KaliLinux'
        - Image|contains|all:
              - ':\Users\'
              - '\AppData\Local\Microsoft\WindowsApps\kali.exe'
    selection_img_windowsapps:
        Image|contains: ':\Program Files\WindowsApps\KaliLinux.'
        Image|endswith: '\kali.exe'
    selection_kali_wsl_parent:
        ParentImage|endswith:
            - '\wsl.exe'
            - '\wslhost.exe'
    selection_kali_wsl_child:
        - Image|contains:
              - '\kali.exe'
              - '\KaliLinux'
        - CommandLine|contains:
              - 'Kali.exe'
              - 'Kali-linux'
              - 'kalilinux'
    filter_main_install_uninstall:
        CommandLine|contains:
            - ' -i '
            - ' --install '
            - ' --unregister '
    condition: 1 of selection_img_* or all of selection_kali_* and not 1 of filter_main_*
falsepositives:
    - Legitimate installation or usage of Kali Linux WSL by administrators or security teams
level: high

Stages and Predicates

Stage 0: `condition`

1 of selection_img_* or all of selection_kali_* and not 1 of filter_main_*

Stage 1: `selection_img_appdata`

selection_img_appdata:
    - Image|contains|all:
          - ':\Users\'
          - '\AppData\Local\packages\KaliLinux'
    - Image|contains|all:
          - ':\Users\'
          - '\AppData\Local\Microsoft\WindowsApps\kali.exe'

Stage 2: `selection_img_windowsapps`

selection_img_windowsapps:
    Image|contains: ':\Program Files\WindowsApps\KaliLinux.'
    Image|endswith: '\kali.exe'

Stage 3: `selection_kali_wsl_parent`

selection_kali_wsl_parent:
    ParentImage|endswith:
        - '\wsl.exe'
        - '\wslhost.exe'

Stage 4: `selection_kali_wsl_child`

selection_kali_wsl_child:
    - Image|contains:
          - '\kali.exe'
          - '\KaliLinux'
    - CommandLine|contains:
          - 'Kali.exe'
          - 'Kali-linux'
          - 'kalilinux'

Stage 5: `not filter_main_install_uninstall`

filter_main_install_uninstall:
    CommandLine|contains:
        - ' -i '
        - ' --install '
        - ' --unregister '

Exclusions

The rule actively suppresses these predicates.

Field	Kind	Excluded values	Search
`CommandLine`	match	`--install`	`excludes:CommandLine` `field:"CommandLine" value:" --install "`
`CommandLine`	match	`--unregister`	`excludes:CommandLine` `field:"CommandLine" value:" --unregister "`
`CommandLine`	match	`-i`	`excludes:CommandLine` `field:"CommandLine" value:" -i "`

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`Kali-linux` `Kali.exe` `kalilinux`	`field:"CommandLine" kind:match`
`Image`	ends_with	`\kali.exe`	`field:"Image" kind:ends_with value:"\kali.exe"`
`Image`	match	`:\Program Files\WindowsApps\KaliLinux.` `:\Users\` corpus 3 (sigma 3) `\AppData\Local\Microsoft\WindowsApps\kali.exe` `\AppData\Local\packages\KaliLinux` `\KaliLinux` `\kali.exe`	`field:"Image" kind:match`
`ParentImage`	ends_with	`\wsl.exe` corpus 4 (sigma 4) `\wslhost.exe` corpus 2 (sigma 2)	`field:"ParentImage" kind:ends_with`

WSL Kali-Linux Usage

Known false positives

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Stage 0: condition

Stage 1: selection_img_appdata

Stage 2: selection_img_windowsapps

Stage 3: selection_kali_wsl_parent

Stage 4: selection_kali_wsl_child

Stage 5: not filter_main_install_uninstall

Exclusions

Indicators

Stage 0: `condition`

Stage 1: `selection_img_appdata`

Stage 2: `selection_img_windowsapps`

Stage 3: `selection_kali_wsl_parent`

Stage 4: `selection_kali_wsl_child`

Stage 5: `not filter_main_install_uninstall`