Detection rules › Sigma
HTML Help HH.EXE Suspicious Child Process
Detects a suspicious child process of a Microsoft HTML Help (HH.exe)
MITRE ATT&CK coverage
Event coverage
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Security-Auditing | Event ID 4688 | A new process has been created. |
Rule body yaml
title: HTML Help HH.EXE Suspicious Child Process
id: 52cad028-0ff0-4854-8f67-d25dfcbc78b4
status: test
description: Detects a suspicious child process of a Microsoft HTML Help (HH.exe)
references:
- https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/chm-badness-delivers-a-banking-trojan/
- https://github.com/elastic/protections-artifacts/commit/746086721fd385d9f5c6647cada1788db4aea95f#diff-27939090904026cc396b0b629c8e4314acd6f5dac40a676edbc87f4567b47eb7
- https://www.ptsecurity.com/ww-en/analytics/pt-esc-threat-intelligence/higaisa-or-winnti-apt-41-backdoors-old-and-new/
- https://www.zscaler.com/blogs/security-research/unintentional-leak-glimpse-attack-vectors-apt37
author: Maxim Pavlunin, Nasreddine Bencherchali (Nextron Systems)
date: 2020-04-01
modified: 2023-04-12
tags:
- attack.execution
- attack.initial-access
- attack.stealth
- attack.t1047
- attack.t1059.001
- attack.t1059.003
- attack.t1059.005
- attack.t1059.007
- attack.t1218
- attack.t1218.001
- attack.t1218.010
- attack.t1218.011
- attack.t1566
- attack.t1566.001
logsource:
category: process_creation
product: windows
detection:
selection:
ParentImage|endswith: '\hh.exe'
Image|endswith:
- '\CertReq.exe'
- '\CertUtil.exe'
- '\cmd.exe'
- '\cscript.exe'
- '\installutil.exe'
- '\MSbuild.exe'
- '\MSHTA.EXE'
- '\msiexec.exe'
- '\powershell.exe'
- '\pwsh.exe'
- '\regsvr32.exe'
- '\rundll32.exe'
- '\schtasks.exe'
- '\wmic.exe'
- '\wscript.exe'
condition: selection
falsepositives:
- Unknown
level: high
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
ParentImage|endswith: '\hh.exe'
Image|endswith:
- '\CertReq.exe'
- '\CertUtil.exe'
- '\cmd.exe'
- '\cscript.exe'
- '\installutil.exe'
- '\MSbuild.exe'
- '\MSHTA.EXE'
- '\msiexec.exe'
- '\powershell.exe'
- '\pwsh.exe'
- '\regsvr32.exe'
- '\rundll32.exe'
- '\schtasks.exe'
- '\wmic.exe'
- '\wscript.exe'
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
Image | ends_with |
|
ParentImage | ends_with |
|