Threat Huntmediumtest

File Download Via Curl.EXE

Detects file download using curl.exe

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Launch
Florian Roth (Nextron Systems)Created Tue Jul 05Updated Tue Feb 219a517fca-4ba3-4629-9278-a68694697b81windows
Hunting Hypothesis
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 Logic2 selectors
detection:
    selection_img:
        - Image|endswith: '\curl.exe'
        - Product: 'The curl executable'
    selection_remote:
        CommandLine|contains:
            - ' -O'  # covers the alias for --remote-name and --output
            - '--remote-name'
            - '--output'
    condition: all of selection_*
False Positives

Scripts created by developers and admins

Administrative activity

The "\Git\usr\bin\sh.exe" process uses the "--output" flag to download a specific file in the temp directory with the pattern "gfw-httpget-xxxxxxxx.txt "