Suspicious Curl File Upload - Linux

detection:
  filter_optional_localhost:
    CommandLine|contains:
      - '://localhost'
      - '://127.0.0.1'
  selection_cli:
    - CommandLine|contains:
        - ' --form'
        - ' --upload-file '
        - ' --data '
        - ' --data-'
    - CommandLine|re: '\s-[FTd]\s'
  selection_img:
    Image|endswith: '/curl'
  condition: all of selection_* and not 1 of filter_optional_*

The rule’s detection, its selections and fields in order of name. The whole rule, with its references and false positives, is on SigmaHQ, by Nasreddine Bencherchali (Nextron Systems), Cedric MAURUGEON (Update), under the Detection Rule License 1.1. CmdID evaluates it on a command line alone: a test on what a command line cannot show, such as the parent process or the user, is not met.

The commands LOLBAS or GTFOBins documents for curl trip it: each is on its program’s page, read by CmdID.