Sigma rule: Arbitrary Command Execution Using WSL

Rule

Title

Arbitrary Command Execution Using WSL

Status

test

Level

medium

Author

oscd.community, Zach Stanford @svch0st, Nasreddine Bencherchali (Nextron Systems)

Date

2020-10-05

Modified

2023-04-12

File

rules-threat-hunting/windows/process_creation/proc_creation_win_wsl_arbitrary_command_execution.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects potential abuse of Windows Subsystem for Linux (WSL) binary as a Living of the Land binary in order to execute arbitrary Linux or Windows commands.

Log source

product

windows

category

process_creation

Detection

selection_img:
    - Image|endswith: '\wsl.exe'
    - OriginalFileName: 'wsl.exe'
selection_cli:
    CommandLine|contains:
        - ' -e '
        - ' --exec'
        - ' --system'
        - ' --shell-type '
        - ' /mnt/c' # Path to mounted "C:\" partition (Indication of running Windows binaries via WSL)
        - ' --user root'
        - ' -u root'
        - '--debug-shell'
filter_main_kill:
    # This filter is to handle a FP that occurs when a process is spawned from WSL and then closed by the user
    # Example would be to open VsCode through it's server extension from WSL
        # GrandparentCommandLine: "C:\Users\XXX\AppData\Local\Programs\Microsoft VS Code\Code.exe" --ms-enable-electron-run-as-node c:\Users\XXX\.vscode\extensions\ms-vscode-remote.remote-wsl-0.72.0\dist\wslDaemon.js
        # ParentCommandLine: C:\WINDOWS\system32\cmd.exe /d /s /c "C:\WINDOWS\System32\wsl.exe -d Ubuntu-20.04 -e kill 1366"
        # CommandLine: C:\WINDOWS\System32\wsl.exe -d Ubuntu-20.04 -e kill 1366
    ParentImage|endswith: '\cmd.exe'
    CommandLine|contains|all:
        - ' -d '
        - ' -e kill '
condition: all of selection_* and not 1 of filter_main_*

False positives (as the rule lists them)

• Automation and orchestration scripts may use this method to execute scripts etc.
• Legitimate use by Windows to kill processes opened via WSL (example VsCode WSL server)

Tags

• attack.execution
• attack.stealth
• attack.t1218
• attack.t1202
• detection.threat-hunting

MITRE ATT&CK ids this rule names

• T1202
• T1218

Related rules

• 2267fe65-0681-42ad-9a6d-46553d3f3480 (similar)

References

• https://lolbas-project.github.io/lolbas/OtherMSBinaries/Wsl/
• https://twitter.com/nas_bench/status/1535431474429808642

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules-threat-hunting/windows/process_creation/proc_creation_win_wsl_arbitrary_command_execution.yml