could mp4 files carry virus?

[brannsiu]

mp4 movie, downloadable from the web, could it carry any virus if it's confirmed to be a playable mp4 file? could there be already any hidden virus running at the background on execution of the file?

 

[13thmonkey]

I would say yes. Imagine a virus who's first job is to allow the playback of the embedded mp4 file, and then it also can deliver payload. Be careful what you download and from where, have good AV, buy content from proper sources.