Sigma rule: HackTool - Defendnot Execution

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-80e41088212e, updated 2026-09-27T00:00:00.000Z.

Rule

Title
HackTool - Defendnot Execution
Status
experimental
Level
high
Author
Swachchhanda Shrawan Poudel (Nextron Systems)
Date
2026-09-27
File
rules/windows/process_creation/proc_creation_win_hktl_defendnot_execution.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects the execution of the hacktool Defendnot. Defendnot is a hacktool that abuses Microsoft undocumented WSC (Windows Security Center) API
to disable Windows Defender by registering itself as a fake antivirus product. Threat actors often use these kind of tools to bypass security measures.

Log source

product
windows
category
process_creation

Detection

selection:
    - Image|contains: 'defendnot'
    - CommandLine|contains:
          - 'defendnot'
          - 'https://dnot.sh/'
    - Hashes|contains:
          - 'IMPHASH=1FAAED26690A9455A795E2215661726F'
          - 'IMPHASH=304786466DE25780347A9DCFAF381EF7'
          - 'IMPHASH=55B10396EA722770E51BC288E62179DB'
          - 'IMPHASH=59D65F5EFACBDB1AA2A6CF745B07C058'
          - 'IMPHASH=6CEDEC3562FEF2DC2F959A1D0BF54DB8'
          - 'IMPHASH=75002197E0D24AAF0B8C6A1BF68513D6'
          - 'IMPHASH=7EC4023C85149450AB388F0837192FE0'
          - 'IMPHASH=CA4A3E08E9410A6AEF018424C64C2641'
condition: selection

False positives (as the rule lists them)

  • Unlikely

Tags

  • attack.defense-impairment
  • attack.t1685

MITRE ATT&CK ids this rule names

Related rules

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/windows/process_creation/proc_creation_win_hktl_defendnot_execution.yml

Sources and licences

  • SigmaHQ

    "HackTool - Defendnot Execution" by Swachchhanda Shrawan Poudel (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_hktl_defendnot_execution.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: HackTool - Defendnot Execution",
entity page, dataset version ref-80e41088212e, updated 2026-09-27T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/0aaa9689-9f38-491d-bd4d-a9af6eb43138 (accessed 2026-11-03).
Underlying source: SigmaHQ rule 0aaa9689-9f38-491d-bd4d-a9af6eb43138, 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.