Detectionmediumtest

Uncommon Assistive Technology Applications Execution Via AtBroker.EXE

Detects the start of a non built-in assistive technology applications via "Atbroker.EXE".

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Launch
Mateusz Wydra, oscd.communityCreated Mon Oct 12Updated Wed Mar 06f24bcaea-0cd1-11eb-adc1-0242ac120002windows
Log Source
WindowsProcess Creation
ProductWindows← raw: windows
CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic
Detection Logic4 selectors
detection:
    selection_img:
        - Image|endswith: '\AtBroker.exe'
        - OriginalFileName: 'AtBroker.exe'
    selection_cli:
        CommandLine|contains: 'start'
    filter_main_builtin:
        CommandLine|contains:
            - 'animations'
            - 'audiodescription'
            - 'caretbrowsing'
            - 'caretwidth'
            - 'colorfiltering'
            - 'cursorindicator'
            - 'cursorscheme'
            - 'filterkeys'
            - 'focusborderheight'
            - 'focusborderwidth'
            - 'highcontrast'
            - 'keyboardcues'
            - 'keyboardpref'
            - 'livecaptions'
            - 'magnifierpane'
            - 'messageduration'
            - 'minimumhitradius'
            - 'mousekeys'
            - 'Narrator'
            - 'osk'
            - 'overlappedcontent'
            - 'showsounds'
            - 'soundsentry'
            - 'speechreco'
            - 'stickykeys'
            - 'togglekeys'
            - 'voiceaccess'
            - 'windowarranging'
            - 'windowtracking'
            - 'windowtrackingtimeout'
            - 'windowtrackingzorder'
    filter_optional_java:
        CommandLine|contains: 'Oracle_JavaAccessBridge'
    condition: all of selection_* and not 1 of filter_main_* and not 1 of filter_optional_*
False Positives

Legitimate, non-default assistive technology applications execution

Rule Metadata
Rule ID
f24bcaea-0cd1-11eb-adc1-0242ac120002
Status
test
Level
medium
Type
Detection
Created
Mon Oct 12
Modified
Wed Mar 06
Path
rules/windows/process_creation/proc_creation_win_atbroker_uncommon_ats_execution.yml
Raw Tags
attack.defense-evasionattack.t1218
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