public cyber tool / public / browser-side

File Extension Risk Checker

Before opening an attachment, check the real extension and double extensions. The tool does not upload files: it only analyzes the name you enter.

inspect --filename local analysis / no remote fetch

inspect --filename

filename or extension

Quick rules

A double-extension file such as `invoice.pdf.exe` must be treated as executable, not as a PDF.

Macro documents, scripts, shortcuts and disk images can execute code or start attack chains.

If the file is unexpected, verify the sender through a separate channel before opening it.

references

CISA malware guidance