The actual extension is .mp4 . However, in many malicious cases, files like this are actually executables (like .exe or .scr ) where the final extension is hidden by Windows settings.

The most critical thing to know is that your computer typically looks at the extension to decide how to open a file.

A high-quality movie file is usually hundreds of megabytes or several gigabytes. If this file is very small (e.g., 1MB to 50MB), it is almost certainly a virus or a downloader, not a video.

Upload the file to VirusTotal . It will scan the file using over 70 different antivirus engines to see if it contains malicious code. 3. How to Properly Play/Convert (If Safe)