Julie.mp4.mkv.mp4 -

Because Windows might hide the .exe extension, the user only sees GreatVideo.mp4 .

A user sees the file name and immediately assumes it is a standard video file. JULIE.mp4.mkv.mp4

The most dangerous application of this naming convention occurs when attackers hide executable files behind harmless media extensions. Because Windows might hide the

By default, operating systems like Microsoft Windows often hide known file extensions to keep the interface looking clean. Malicious actors exploit this default setting to engineer visual traps: JULIE.mp4.mkv.mp4

If you downloaded a file from an untrusted source, right-click it and run a scan with your antivirus software before double-clicking it.