Detectionmediumtest

File Download From IP URL Via Curl.EXE

Detects file downloads directly from IP address URL using curl.exe

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Nasreddine Bencherchali (Nextron Systems)Created Wed Oct 189cc85849-3b02-4cb5-b371-3a1ff54f2218windows

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_img:
        - Image|endswith: '\curl.exe'
        - OriginalFileName: 'curl.exe'
    selection_ip:
        CommandLine|re: '://[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}'
    selection_http:
        CommandLine|contains: 'http'
    selection_flag:
        CommandLine|contains:
            - ' -O'  # covers the alias for --remote-name and --output
            - '--remote-name'
            - '--output'
    filter_main_ext:
        # Note: This filter exists to avoid duplication with 5cb299fc-5fb1-4d07-b989-0644c68b6043
        CommandLine|endswith:
            - '.bat'
            - '.bat"'
            - '.dat'
            - '.dat"'
            - '.dll'
            - '.dll"'
            - '.exe'
            - '.exe"'
            - '.gif'
            - '.gif"'
            - '.hta'
            - '.hta"'
            - '.jpeg'
            - '.jpeg"'
            - '.log'
            - '.log"'
            - '.msi'
            - '.msi"'
            - '.png'
            - '.png"'
            - '.ps1'
            - '.ps1"'
            - '.psm1'
            - '.psm1"'
            - '.vbe'
            - '.vbe"'
            - '.vbs'
            - '.vbs"'
            - ".bat'"
            - ".dat'"
            - ".dll'"
            - ".exe'"
            - ".gif'"
            - ".hta'"
            - ".jpeg'"
            - ".log'"
            - ".msi'"
            - ".png'"
            - ".ps1'"
            - ".psm1'"
            - ".vbe'"
            - ".vbs'"
    condition: all of selection_* and not 1 of filter_main_*