Delete Defender Scan ShellEx Context Menu Registry Key
Detects deletion of registry key that adds 'Scan with Defender' option in context menu. Attackers may use this to make it harder for users to scan files that are suspicious.
Sigma rule (View on GitHub)
1title: Delete Defender Scan ShellEx Context Menu Registry Key
2id: 72a0369a-2576-4aaf-bfc9-6bb24a574ac6
3related:
4 - id: b9e8c7d6-a5f4-4e3d-8b1a-9f0c8d7e6a5b
5 type: similar
6status: experimental
7description: Detects deletion of registry key that adds 'Scan with Defender' option in context menu. Attackers may use this to make it harder for users to scan files that are suspicious.
8references:
9 - https://research.splunk.com/endpoint/395ed5fe-ad13-4366-9405-a228427bdd91/
10 - https://winaero.com/how-to-delete-scan-with-windows-defender-from-context-menu-in-windows-10/
11 - https://thedfirreport.com/2021/10/18/icedid-to-xinglocker-ransomware-in-24-hours/
12 - https://blog.malwarebytes.com/malwarebytes-news/2021/02/lazyscripter-from-empire-to-double-rat/
13author: 'Matt Anderson (Huntress)'
14date: 2025-07-11
15tags:
16 - attack.defense-evasion
17logsource:
18 category: registry_delete
19 product: windows
20detection:
21 selection:
22 TargetObject|contains: 'shellex\ContextMenuHandlers\EPP'
23 condition: selection
24falsepositives:
25 - Unlikely as this weakens defenses and normally would not be done even if using another AV.
26level: medium
References
Related rules
- Disabling Windows Defender WMI Autologger Session via Reg.exe
- PowerShell Defender Threat Severity Default Action Set to 'Allow' or 'NoAction'
- Windows Defender Context Menu Removed
- Windows Defender Threat Severity Default Action Modified
- Unsigned DLL Loaded by Windows Utility