Detectionhighexperimental

AMSI Disabled via Registry Modification

Detects attempts to disable AMSI (Anti-Malware Scan Interface) by modifying the AmsiEnable registry value. Anti-Malware Scan Interface (AMSI) is a security feature in Windows that allows applications and services to integrate with anti-malware products for enhanced protection against malicious content. Adversaries may attempt to disable AMSI to evade detection by security software, allowing them to execute malicious scripts or code without being scanned.

Convert In Phoenix Studio

Open this Sigma rule in the converter with the YAML preloaded and ready for backend selection.

Launch
Swachchhanda Shrawan Poudel (Nextron Systems)Created Thu Dec 25aa37cbb0-da36-42cb-a90f-fdf216fc7467windows
Log Source
WindowsRegistry Set
ProductWindows← raw: windows
CategoryRegistry Set← raw: registry_set
Detection Logic
Detection Logic1 selector
detection:
    selection:
        TargetObject|endswith: '\Software\Microsoft\Windows Script\Settings\AmsiEnable'
        Details: 'DWORD (0x00000000)'
    condition: selection
False Positives
Unlikely

False positives are unlikely for most environments. High confidence detection.

Testing & Validation

Simulations

atomic-red-teamT1562.001
View on ART

AMSI Bypass - Create AMSIEnable Reg Key

GUID: 728eca7b-0444-4f6f-ac36-437e3d751dc0

Regression Tests

by Swachchhanda Shrawan Poudel (Nextron Systems)
Positive Detection Test1 matchevtx

Microsoft-Windows-Sysmon