Windows: Rundll32 Launching NSIS Module for Stealer Capability
Alerts on rundll32.exe execution tied to NSIS module loading indicators (nsis_uns and PrintUIEntry) in the command line.
- Product
- windows
- Category
- process_creation
- Author
- TropChaud (SigmaHQ), DRL 1.1
- Published
- 2023-01-26
- Updated
- 2026-07-31
ATT&CK techniques
Defense EvasionRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule flags process creation where Rundll32.EXE is used to load a module associated with an NSIS artifact, indicated by the presence of specific NSIS-related and export-function strings in the command line. Attackers often use Rundll32 to blend malicious DLL/module execution into legitimate Windows behavior. Detection relies on Windows process creation telemetry including the OriginalFileName and command-line arguments.
Reporting behind it
- elis531989.medium.comhttps://elis531989.medium.com/dancing-with-shellcodes-analyzing-rhadamanthys-stealer-3c4986966a88
- blog.cyble.comhttps://blog.cyble.com/2023/01/12/rhadamanthys-new-stealer-spreading-through-google-ads/
- joesandbox.comhttps://www.joesandbox.com/analysis/790122/0/html
- twitter.comhttps://twitter.com/anfam17/status/1607477672057208835
- github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2023/Malware/Rhadamanthys/proc_creation_win_malware_rhadamanthys_stealer_dll_launch.yml
Changelog
v5- v5Candidate ingested via manual entry.2026-07-31
- v4Candidate ingested via manual entry.2026-07-31
- v3Candidate ingested via manual entry.2026-07-31
- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: "Windows: Rundll32 Launching NSIS Module for Stealer Capability"
id: 95b9b4c4-e7d5-4338-ac81-36395194e3ed
status: test
description: This rule flags process creation where Rundll32.EXE is used to load a module associated with an NSIS artifact, indicated by the presence of specific NSIS-related and export-function strings in the command line. Attackers often use Rundll32 to blend malicious DLL/module execution into legitimate Windows behavior. Detection relies on Windows process creation telemetry including the OriginalFileName and command-line arguments.
references:
- https://elis531989.medium.com/dancing-with-shellcodes-analyzing-rhadamanthys-stealer-3c4986966a88
- https://blog.cyble.com/2023/01/12/rhadamanthys-new-stealer-spreading-through-google-ads/
- https://www.joesandbox.com/analysis/790122/0/html
- https://twitter.com/anfam17/status/1607477672057208835
- https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2023/Malware/Rhadamanthys/proc_creation_win_malware_rhadamanthys_stealer_dll_launch.yml
author: TropChaud, Huntrule Team
date: 2023-01-26
modified: 2023-02-05
tags:
- attack.stealth
- attack.t1218.011
- detection.emerging-threats
logsource:
category: process_creation
product: windows
detection:
selection_rundll32:
- OriginalFileName: RUNDLL32.EXE
- Image|endswith: \rundll32.exe
selection_dll:
CommandLine|contains: nsis_uns
selection_export_function:
CommandLine|contains: PrintUIEntry
condition: all of selection_*
falsepositives:
- Unknown
level: medium
license: DRL-1.1
related:
- id: 5cdbc2e8-86dd-43df-9a1a-200d4745fba5
type: derived