IMPORTANT: No additional bug fixes or documentation updates
will be released for this version. For the latest information, see the
current release documentation.
Network Connection via Compiled HTML File
editNetwork Connection via Compiled HTML File
editCompiled 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: eql
Rule indices:
- winlogbeat-*
- logs-endpoint.events.*
- logs-windows.*
Severity: low
Risk score: 21
Runs every: 5m
Searches indices from: now-9m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Host
- Windows
- Threat Detection
- Execution
Version: 102
Rule authors:
- Elastic
Rule license: Elastic License v2
Rule query
editsequence by process.entity_id
[process where host.os.type == "windows" and process.name : "hh.exe" and event.type == "start"]
[network where host.os.type == "windows" and process.name : "hh.exe" and
not cidrmatch(destination.ip, "10.0.0.0/8", "127.0.0.0/8", "169.254.0.0/16", "172.16.0.0/12", "192.0.0.0/24",
"192.0.0.0/29", "192.0.0.8/32", "192.0.0.9/32", "192.0.0.10/32", "192.0.0.170/32", "192.0.0.171/32",
"192.0.2.0/24", "192.31.196.0/24", "192.52.193.0/24", "192.168.0.0/16", "192.88.99.0/24", "224.0.0.0/4",
"100.64.0.0/10", "192.175.48.0/24","198.18.0.0/15", "198.51.100.0/24", "203.0.113.0/24", "240.0.0.0/4", "::1",
"FE80::/10", "FF00::/8")]
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Execution
- ID: TA0002
- Reference URL: https://attack.mitre.org/tactics/TA0002/
-
Technique:
- Name: User Execution
- ID: T1204
- Reference URL: https://attack.mitre.org/techniques/T1204/
-
Sub-technique:
- Name: Malicious File
- ID: T1204.002
- Reference URL: https://attack.mitre.org/techniques/T1204/002/
-
Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
-
Technique:
- Name: System Binary Proxy Execution
- ID: T1218
- Reference URL: https://attack.mitre.org/techniques/T1218/
-
Sub-technique:
- Name: Compiled HTML File
- ID: T1218.001
- Reference URL: https://attack.mitre.org/techniques/T1218/001/