Suspicious Curl File Upload - Linux
This rule detects suspicious usage of the 'curl' command on Linux systems that indicates a file upload or data transfer to a web service. It specifically looks for the 'curl' executable being run with command-line arguments such as '--form', '--upload-file', '--data', or their variations ('--data-ascii', '--data-binary', '--data-raw', '--data-urlencode'), or the shorthand options '-F', '-T', '-d'. The rule filters out connections to localhost or 127.0.0.1 to reduce false positives from legitimate local development or testing activities.
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