Detectionmediumtest

Amsi.DLL Loaded Via LOLBIN Process

Detects loading of "Amsi.dll" by a living of the land process. This could be an indication of a "PowerShell without PowerShell" attack

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Launch
Nasreddine Bencherchali (Nextron Systems)Created Thu Jun 01Updated Tue Oct 076ec86d9e-912e-4726-91a2-209359b999b9windows
Log Source
WindowsImage Load (DLL)
ProductWindows← raw: windows
CategoryImage Load (DLL)← raw: image_load
Detection Logic
Detection Logic1 selector
detection:
    selection:
        ImageLoaded|endswith: '\amsi.dll'
        Image|endswith:
            # TODO: Add more interesting processes
            - '\ExtExport.exe'
            - '\odbcconf.exe'
            # - '\regsvr32.exe' # legitimately calls amsi.dll
            - '\rundll32.exe'
    condition: selection
False Positives
Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

References
1
Resolving title…
Internal Research
2
Resolving title…
paloaltonetworks.com
MITRE ATT&CK
Rule Metadata
Rule ID
6ec86d9e-912e-4726-91a2-209359b999b9
Status
test
Level
medium
Type
Detection
Created
Thu Jun 01
Modified
Tue Oct 07
Path
rules/windows/image_load/image_load_dll_amsi_suspicious_process.yml
Raw Tags
attack.defense-evasion
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