file extension vs magic byte mismatch scanner — free browser tool | fatcousin

drop file listing with hashes or paste file paths and first bytes · detect files with extensions inconsistent with their actual content type · identify renamed malware and hidden payloads · surface extension-based camouflage · runs locally

csv / binaries

drop file listing csv or binaries (multi-file)

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csv columns: path + first bytes hex · or drop files for header-only batch scan · 500+ magic signatures

drop file listing csv or binaries (multi-file)

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