Detection rules › Splunk
Windows NetSupport RMM DLL Loaded By Uncommon Process
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).
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Defense Evasion | T1036 Masquerading |
Event coverage
| Provider | Event ID | Title |
|---|---|---|
| Sysmon | 7 | Image loaded |
Stages and Predicates
Stage 1: search
search NOT Image IN ("C:\\Program Files (x86)\\*", "C:\\Program Files\\*") EventCode=7 ImageLoaded IN ("*\\CryptPak.dll", "*\\HTCTL32.DLL", "*\\PCICL32.DLL", "*\\TCCTL32.DLL", "*\\pcicapi.dll", "*\\pcichek.dll") Signature="NetSupport Ltd*"
Stage 2: fillnull
fillnull
Stage 3: stats
stats BY Image, ImageLoaded, dest, loaded_file, loaded_file_path, original_file_name, process_exec, process_guid, process_hash, process_id, process_name, process_path, service_dll_signature_exists, service_dll_signature_verified, signature, signature_id, user_id, vendor_product
Stage 4: search
search
Stage 5: search
search
Stage 6: search
search `macro`
Exclusions
Top-level NOT(...) conjuncts — predicates this rule actively suppresses.
| Stage | Field | Kind | Excluded values |
|---|---|---|---|
| 1 | Image | in | "C:\\Program Files (x86)\\*", "C:\\Program Files\\*" |
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 |
|---|---|---|
EventCode | eq |
|
ImageLoaded | in |
|
Signature | eq |
|
Neighbors
Broader alternatives (more inclusive than this rule)
These rules match a superset of what this rule catches. They cover the same events plus more. Use them if you want wider coverage and can absorb more false positives.
- Windows Remote Access Software BRC4 Loaded Dll (drops 3 filters this rule applies)