Detectionmediumtest

ScreenSaver Registry Key Set

Detects registry key established after masqueraded .scr file execution using Rundll32 through desk.cpl

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Jose Luis Sanchez MartinezCreated Wed May 04Updated Thu Aug 1740b6e656-4e11-4c0c-8772-c1cc6dae34cewindows
Log Source
WindowsRegistry Set
ProductWindows← raw: windows
CategoryRegistry Set← raw: registry_set
Detection Logic
Detection Logic3 selectors
detection:
    selection:
        Image|endswith: '\rundll32.exe'
    registry:
        TargetObject|contains: '\Control Panel\Desktop\SCRNSAVE.EXE'
        Details|endswith: '.scr'
    filter:
        Details|contains:
            - 'C:\Windows\System32\'
            - 'C:\Windows\SysWOW64\'
    condition: selection and registry and not filter
False Positives

Legitimate use of screen saver

MITRE ATT&CK
Rule Metadata
Rule ID
40b6e656-4e11-4c0c-8772-c1cc6dae34ce
Status
test
Level
medium
Type
Detection
Created
Wed May 04
Modified
Thu Aug 17
Path
rules/windows/registry/registry_set/registry_set_scr_file_executed_by_rundll32.yml
Raw Tags
attack.defense-evasionattack.t1218.011
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