The SIEM app is now a part of the Elastic Security solution. Click here to view the current documentation.
IMPORTANT: No additional bug fixes or documentation updates will be released for this version.
« Network Connection via Certutil Network Connection via MsXsl »
Elastic Docs ›SIEM Guide [7.8] ›Detections (beta) ›Prebuilt rule reference

Network Connection via Compiled HTML File

edit
IMPORTANT: This documentation is no longer updated. Refer to Elastic's version policy and the latest documentation.

Network Connection via Compiled HTML File

edit

Compiled HTML files (.chm) are commonly distributed as part of the Microsoft HTML Help system. Adversaries may conceal malicious code in a CHM file and deliver it to a victim for execution. CHM content is loaded by the HTML Help executable program (hh.exe).

Rule type: query

Rule indices:

  • winlogbeat-*

Severity: low

Risk score: 21

Runs every: 5 minutes

Searches indices from: now-6m (Date Math format, see also Additional look-back time)

Maximum signals per execution: 100

Tags:

  • Elastic
  • Windows

Version: 2 (version history)

Added (Elastic Stack release): 7.6.0

Last modified (Elastic Stack release): 7.7.0

Rule query

edit
process.name:hh.exe and event.action:"Network connection detected
(rule: NetworkConnect)" and not destination.ip:(10.0.0.0/8 or
172.16.0.0/12 or 192.168.0.0/16)

Threat mapping

edit

Framework: MITRE ATT&CKTM

Rule version history

edit
Version 2 (7.7.0 release)

Updated query, changed from: 

process.name:hh.exe and event.action:"Network connection detected
(rule: NetworkConnect)" and not destination.ip:10.0.0.0/8 and not
destination.ip:172.16.0.0/12 and not destination.ip:192.168.0.0/16
« Network Connection via Certutil Network Connection via MsXsl »