If you have encountered a file with this exact name and are considering downloading it, keep these standard safety tips in mind:
It is often found in older web archives or "abandonware" forums where files were named concisely to save character space. Vdx 4 Ev mp4
A standard MP4 for a 3-minute song should be between 20MB and 100MB. If it is significantly smaller (KB) or larger (GB), it may be suspicious. If you have encountered a file with this