How to detect files that lie about their extension
- Step 1Drop the file — Upload any file — even one you don't trust.
- Step 2Validate — First bytes are read; file-type library matches against signatures.
- Step 3See the report — Detected vs. claimed extension; warning if mismatch.
Frequently asked questions
Is this enough to detect all malware?+
No — it catches the most common disguise (extension mismatch). Use proper antivirus alongside for full coverage.
What if no signature matches?+
The tool reports 'unknown' — could be a custom format, encrypted blob, or text file with no magic bytes.
Why is this important?+
Modern OSes hide extensions by default. Files like 'invoice.pdf.exe' look like PDFs to users but execute as binaries on click.
Privacy first
Every JAD Security operation runs entirely in your browser. Files, passwords, and PGP private keys never leave your device — verified by zero outbound network requests during processing.