Hello!\n\nSorry if this is wrong place to post.\n\nI have a likely stupid sounding question, but coming from Windows background, I believe danger from everything.\n\nI'm usually very paranoid, but was tired at one point, real life stress making me crack, I did something stupid - I downloaded some video files that were hosted in [URL]https://openload.co/f/[/URL]\n\nI pretty much regretted my lack of carefulness few days later and deleted them. Issue being, I also had moved them to external hard drive and deleted them from there as well.\n\nBut now I'm struggling with paranoia and regret of that one time letting my impulses get out of control.\n\nSo my questions are as follow:\n\n1) Is there Mac malware that hides itself inside .mp4 files? Like the file is video file that was expected and it plays, but could something malicious sneak in with it and run in the background without user noticing it? Can Mac malware hide itself inside of mp4 or even image files?\n\nAre there Mac malware/adware/trojans, that can mask themselves with for example .mp4 file extension and when user clicks, it already runs and/or installs something?\n\nFor example catvideo.mp4 is instead installer to malware/trojan? Wouldn't there be some window asking about installing or can it just run/install without asking user's allowance?\n\n\nOr is there a possibility user downloads a video.mp4, clicks on it, video plays normally, but in background something malicious, without user noticing, activates when video was activated?\n\n2) Mac lacks malware that can infect other files, yes? So when I put them on external hard drive, then deleted them, even if there was something malicious, other files there would not have been infected? And using uploading to Mac from that external hard drive would not be a threat?\n\n3) Does Mac malware actually have to ask user to let it run or can it simply sneak in and start running right away?