What problem does it solve? In CTF sandbox challenges, the decisive vulnerability often hides in how an uploaded file flows through backend processing stages. This Skill provides a structured methodology for following a file from ingress through archive extraction, format conversion, parser invocation, and deserialization, so you can pinpoint exactly where backend behavior diverges from user-visible validation. ## Core Features & Use Cases - Ingress and Derivation Mapping: Record request shape, multipart fields, MIME types, temp paths, storage keys, and every derived artifact such as extracted archive members, previews, and thumbnails. - Parser Boundary Tracing: Identify which parser, converter, extractor, or deserializer runs at each step and what drives its branch decisions (extension, MIME, magic bytes, schema). - Decisive Chain Reduction: Compress findings into the smallest replayable sequence from upload to backend effect, and classify whether the weakness lives in archive handling, MIME inference, conversion, path resolution, or deserialization. - Use Case: During a CTF web challenge with a file import feature, use this Skill to trace how an uploaded archive reaches a backend deserializer, preserving each intermediate artifact as evidence for the exploit chain. ## Quick Start Ask the assistant to trace how an uploaded file flows through extraction, conversion, and parsing stages in the current CTF challenge after the sandbox orchestrator has established assumptions.
