Detection: Windows NetSupport RMM DLL Loaded By Uncommon Process

Updated Date: 2025-11-20 ID: 125f96f9-6f34-418b-b868-c4a8d7fb865f Author: Teoderick Contreras, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic detects the loading of specific dynamic-link libraries (DLLs) associated with the NetSupport Remote Manager (RMM) tool by any process on a Windows system. Modules such as CryptPak.dll, HTCTL32.DLL, IPCTL32.DLL, keyshowhook.dll, pcicapi.DLL, PCICL32.DLL, and TCCTL32.DLL, are integral to NetSupport's functionality. This detection is particularly valuable when these modules are loaded by processes running from unusual directories (e.g., Downloads, ProgramData, or user-specific folders) rather than the legitimate Program Files installation path, or by executables that have been renamed but retain the internal "client32" identifier. This helps to identify instances where the legitimate NetSupport tool is being misused by adversaries as a Remote Access Trojan (RAT).

Search

 1`sysmon`
 2EventCode=7
 3ImageLoaded IN (
 4  "*\\CryptPak.dll",
 5  "*\\HTCTL32.DLL",
 6  "*\\pcicapi.dll",
 7  "*\\pcichek.dll",
 8  "*\\PCICL32.DLL",
 9  "*\\TCCTL32.DLL"
10)
11NOT Image IN ("C:\\Program Files\\*", "C:\\Program Files (x86)\\*")
12Signature = "NetSupport Ltd*"
13
14| fillnull
15
16| stats count min(_time) as firstTime max(_time) as lastTime
17  by Image ImageLoaded dest loaded_file loaded_file_path original_file_name process_exec
18     process_guid process_hash process_id process_name process_path service_dll_signature_exists
19     service_dll_signature_verified signature signature_id user_id vendor_product
20
21| `security_content_ctime(firstTime)`
22
23| `security_content_ctime(lastTime)`
24
25| `windows_netsupport_rmm_dll_loaded_by_uncommon_process_filter`

Data Source

Name	Platform	Sourcetype	Source
Sysmon EventID 7	Windows	`'XmlWinEventLog'`	`'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'`

Macros Used

Name	Value
security_content_ctime	`convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)`
windows_netsupport_rmm_dll_loaded_by_uncommon_process_filter	`search *`

windows_netsupport_rmm_dll_loaded_by_uncommon_process_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK

+ Kill Chain Phases

+ NIST

+ CIS

- Threat Actors

ID	Technique	Tactic
T1036	Masquerading	Defense Evasion

Exploitation

DE.AE

CIS 10

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting	Value
Disabled	true
Cron Schedule	`0 * * * *`
Earliest Time	`-70m@m`
Latest Time	`-10m@m`
Schedule Window	`auto`
Creates Risk Event	True

This configuration file applies to all detections of type anomaly. These detections will use Risk Based Alerting.

Implementation

To successfully implement this search, you need to be ingesting logs with the process name and ImageLoaded executions from your endpoints. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA.

Known False Positives

NetSupport RMM installations outside of the standard Program Files directory will trigger this detection. Apply appropriate filters to exclude known legitimate installations.

Associated Analytic Story

NetSupport RMM Tool Abuse

Risk Based Analytics (RBA)

Risk Message:

The following module $ImageLoaded$ was loaded by a non-standard application on endpoint $dest$

Risk Object	Risk Object Type	Risk Score	Threat Objects
dest	system	30	Image

References

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-Sysmon/Operational`	`XmlWinEventLog`
Integration	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-Sysmon/Operational`	`XmlWinEventLog`

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub | Version: 1