Detectionmediumtest

Writing Of Malicious Files To The Fonts Folder

Monitors for the hiding possible malicious files in the C:\Windows\Fonts\ location. This folder doesn't require admin privillege to be written and executed from.

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SreemanCreated Tue Apr 21Updated Tue Mar 08ae9b0bd7-8888-4606-b444-0ed7410cb728windows

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:
    selection_1:
        CommandLine|contains:
            - 'echo'
            - 'copy'
            - 'type'
            - 'file createnew'
            - 'cacls'
    selection_2:
        CommandLine|contains: 'C:\Windows\Fonts\'
    selection_3:
        CommandLine|contains:
            - '.sh'
            - '.exe'
            - '.dll'
            - '.bin'
            - '.bat'
            - '.cmd'
            - '.js'
            - '.msh'
            - '.reg'
            - '.scr'
            - '.ps'
            - '.vb'
            - '.jar'
            - '.pl'
            - '.inf'
            - '.cpl'
            - '.hta'
            - '.msi'
            - '.vbs'
    condition: all of selection_*