Sigma rule: Potential Notepad++ CVE-2025-49144 Exploitation

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-9e92fe67a77b, updated 2025-06-26T00:00:00.000Z.

Rule

Title
Potential Notepad++ CVE-2025-49144 Exploitation
Status
experimental
Level
high
Author
Swachchhanda Shrawan Poudel (Nextron Systems)
Date
2025-06-26
File
rules-emerging-threats/2025/Exploits/CVE-2025-49144/proc_creation_win_exploit_cve_2025_49144.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects potential exploitation of CVE-2025-49144, a local privilege escalation vulnerability in Notepad++ installers (v8.8.1 and prior) where the installer calls regsvr32.exe without specifying the full path.
This allows an attacker to execute arbitrary code with elevated privileges by placing a malicious regsvr32.exe alongside this Legitimate Notepad++ installer.
The vulnerability is triggered when the installer attempts to register the NppShell.dll file, which is a component of Notepad++.

Log source

product
windows
category
process_creation

Detection

selection:
    Image|endswith: '\regsvr32.exe'
    CommandLine|startswith: 'regsvr32 /s'
    CommandLine|contains: '\contextMenu\NppShell.dll'
filter_main_legit_regsvr32:
    Image:
        - 'C:\Windows\System32\regsvr32.exe'
        - 'C:\Windows\SysWOW64\regsvr32.exe'
condition: selection and not 1 of filter_main_*

False positives (as the rule lists them)

  • Unknown

Tags

  • attack.persistence
  • attack.privilege-escalation
  • attack.execution
  • attack.stealth
  • attack.t1574.008
  • cve.2025-49144
  • detection.emerging-threats

CVEs this rule names

MITRE ATT&CK ids this rule names

References

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules-emerging-threats/2025/Exploits/CVE-2025-49144/proc_creation_win_exploit_cve_2025_49144.yml

Sources and licences

  • SigmaHQ

    "Potential Notepad++ CVE-2025-49144 Exploitation" by Swachchhanda Shrawan Poudel (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules-emerging-threats/2025/Exploits/CVE-2025-49144/proc_creation_win_exploit_cve_2025_49144.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Potential Notepad++ CVE-2025-49144 Exploitation",
entity page, dataset version ref-9e92fe67a77b, updated 2025-06-26T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/933f0bb5-0681-4fe7-8a17-4e6cccbaac44 (accessed 2026-11-03).
Underlying source: SigmaHQ rule 933f0bb5-0681-4fe7-8a17-4e6cccbaac44, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.