Detection rules › Splunk
Detect MSHTA Url in Command Line
The following analytic detects the use of Microsoft HTML Application Host (mshta.exe) to make remote HTTP or HTTPS connections. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line arguments containing URLs. This activity is significant because adversaries often use mshta.exe to download and execute remote .hta files, bypassing security controls. If confirmed malicious, this behavior could allow attackers to execute arbitrary code, potentially leading to system compromise, data exfiltration, or further network infiltration.
Known false positives
- It is possible legitimate applications may perform this behavior and will need to be filtered.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Stealth |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 1: Process creation |
| Security-Auditing | Event ID 4688: A new process has been created. |
Rule body
name: Detect MSHTA Url in Command Line
id: 9b3af1e6-5b68-11eb-ae93-0242ac130002
version: 21
creation_date: '2020-04-29'
modification_date: '2026-07-20'
author: Michael Haag, Splunk
status: production
type: TTP
description: The following analytic detects the use of Microsoft HTML Application Host (mshta.exe) to make remote HTTP or HTTPS connections. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line arguments containing URLs. This activity is significant because adversaries often use mshta.exe to download and execute remote .hta files, bypassing security controls. If confirmed malicious, this behavior could allow attackers to execute arbitrary code, potentially leading to system compromise, data exfiltration, or further network infiltration.
data_source:
- Sysmon EventID 1
- Windows Event Log Security 4688
- CrowdStrike ProcessRollup2
- Cisco Network Visibility Module Flow Data
search: |-
| tstats `security_content_summariesonly` count values(Processes.process) as process values(Processes.parent_process) as parent_process min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes
WHERE `process_mshta` (Processes.process="*http://*"
OR
Processes.process="*https://*")
BY Processes.action Processes.dest Processes.original_file_name
Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
Processes.process Processes.process_exec Processes.process_guid
Processes.process_hash Processes.process_id Processes.process_integrity_level
Processes.process_name Processes.process_path Processes.user
Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `detect_mshta_url_in_command_line_filter`
how_to_implement: The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint` data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.
known_false_positives: It is possible legitimate applications may perform this behavior and will need to be filtered.
references:
- https://github.com/redcanaryco/AtomicTestHarnesses
- https://redcanary.com/blog/introducing-atomictestharnesses/
- https://docs.microsoft.com/en-us/windows/win32/search/-search-3x-wds-extidx-prot-implementing
- https://denwp.com/dissecting-lumma-malware/
- https://www.mcafee.com/blogs/other-blogs/mcafee-labs/behind-the-captcha-a-clever-gateway-of-malware/
finding:
title: An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$ attempting to access a remote destination to download an additional payload.
entity:
field: user
type: user
score: 50
intermediate_findings:
entities:
- field: dest
type: system
score: 50
message: An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$ attempting to access a remote destination to download an additional payload.
threat_objects:
- field: parent_process_name
type: parent_process_name
- field: process_name
type: process_name
analytic_story:
- APT37 Rustonotto and FadeStealer
- Compromised Windows Host
- Lumma Stealer
- Living Off The Land
- Suspicious MSHTA Activity
- XWorm
- Cisco Network Visibility Module Analytics
- NetSupport RMM Tool Abuse
- Starland RAT Campaign
asset_type: Endpoint
mitre_attack_id:
- T1218.005
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
category: endpoint
security_domain: endpoint
Stages and Predicates
Stage 1: tstats
| tstats `security_content_summariesonly` count values(Processes.process) as process values(Processes.parent_process) as parent_process min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes
WHERE `process_mshta` (Processes.process="*http://*"
OR
Processes.process="*https://*")
BY Processes.action Processes.dest Processes.original_file_name
Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
Processes.process Processes.process_exec Processes.process_guid
Processes.process_hash Processes.process_id Processes.process_integrity_level
Processes.process_name Processes.process_path Processes.user
Processes.user_id Processes.vendor_product
Stage 2: search
| `drop_dm_object_name(Processes)`
Stage 3: search
| `security_content_ctime(firstTime)`
Stage 4: search
| `security_content_ctime(lastTime)`
Stage 5: search
| `detect_mshta_url_in_command_line_filter`
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
Processes.original_file_name | eq |
| field:"OriginalFileName" kind:eq |
Processes.process | eq |
| field:"CommandLine" kind:eq |
Processes.process_name | eq |
| field:"process_name" kind:eq |