Downloaded, then deleted video files (mp4) - how to make sure I'm safe?

[Aiumu]

So I'm usually careful, but got bit drunk and ended up downloading some naughty mp4 video files from direct download file upload site. And of course made copies and put them on external hard drive.

Come next day and hangover, cursed myself, deleted all videos from Mac and external hard drive.

Ran Malwarebytes, everything seems to be fine.

What else should I do (besides not getting drunk again...)?
The video files played all normally and were what I expected them to be.

1) Could I be infected? Will Malwarebytes find anything if there is anything to find?

2) Could my external drive and all my good normal files be infected? Could I infect other Mac systems with those files from external hard drive?

3) Could normally working mp4 video file contain something bad?

4) Could normally working mp4 video file leave something bad behind after I deleted it?

In short, how likely could my Mac and External Hard Drive be infected and would running Malwarebytes be enough to find everything if there is anything?

 

[honestone]

If you just stored them on your external drive (and did not play them from that drive), and then deleted them, that drive should be fine.

Regarding your machine itself, are you making backups to an external device? If you are, what software are you using for that, and did you do any backups after downloading those files?

If you have a backup before you downloaded them, then you could 1) use Disk Utility to Erase and Format your internal drive, 2) do a clean, "virgin" installation of whatever Mac OS you are using, and 3) use Migration Assistant to "migrate"/copy stuff from your good, clean backup.

On the surface, being you did not experience anything "bad" when you viewed those videos, you should be OK. But that might not be a guarantee.

 

[Aiumu]

If you just stored them on your external drive, and then deleted them, that drive should be fine.

Regarding your machine itself, are you making backups to an external device? If you are, what software are you using for that, and did you do any backups after downloading those files?

If you have a backup before you downloaded them, then you could 1) use Disk Utility to Erase and Format your internal drive, 2) do a clean, "virgin" installation of whatever Mac OS you are using, and 3) use Migration Assistant to "migrate"/copy stuff from your good, clean backup.

I did open few of them on external drive to see if they worked - is that bad? ALL videos worked like they were meant to so not sure if they could have hidden something bad. I'm not very experienced with Mac.

Nope, no back up. I've been busy after getting this Mac and neglected doing system back up, just storing files in external hard drive.

 

[honestone]

No backup is not a good thing. Also, what exactly do you mean by:

"ALL videos worked like they were meant to".

 

[Aiumu]

No backup is not a good thing. Also, what exactly do you mean by:

"ALL videos worked like they were meant to".

I'm going to have to buy new external hard drive for system backup, the one I'm using now is kind of multi-purpose file container that has not enough room.
Any advice for external hard drive brands?

They worked like videos they were promised to be. I was wondering if they were malware, would they have worked like real videos as if it is possible Mac malware could hide inside actual video file?

 

[honestone]

Well, if you feel "the need for speed", an SSD drive would be the way to go, although they are expensive (but going down in price). How large is your internal drive now, and how much space are you using? For an SSD drive, ones made by Samsung are the best (yeah, even though Apple and Samsung are "duking it out" over cell phones). And you can purchase an inexpensive, slim Orico external enclosure and install the drive yourself. That is what I did with my recent purchase of two Samsung 512 gig SSDs. They are fast! And I will be taking one of them when we go to London next month, so that I can watch videos (TV series and/or movies) on the flights back and forth.

For standard HDDs, ones manufactured by Seagate are the best. I would definitely recommend getting one for which the drive spins at 7200 rpm. 5400 rpm is just too slow.

As for malware hiding inside a video file, it is possible, althoughMac-specific viruses are certainly not as common as ones in the Windows world. Malwarebytes is a good start, but it's not a cure all. This link shows the differences between the 2 versions of that software:

https://buy.malwarebytes.com/us/?ht...arebytes.com&gclid=CLnWktDN-dECFUuXfgod3sQPLA

Note that for the free trial version, 4 of its features expire after 14 days. If you really want to be sure, you could download and run Sophos:

https://www.google.com/search?q=Sop...69i57j69i59.2855j0j4&sourceid=chrome&ie=UTF-8

Another knowledgeable user here recommended it. I have used it in the past, and it worked fine, as I was having an issue with some "Bitcoin-related" malware, even though I have never used Bitcoins. Hopefully, he'll "chime in" here.

 

[Aiumu]

Well, if you feel "the need for speed", an SSD drive would be the way to go, although they are expensive (but going down in price). How large is your internal drive now, and how much space are you using? For an SSD drive, ones made by Samsung are the best (yeah, even though Apple and Samsung are "duking it out" over cell phones). And you can purchase an inexpensive, slim Orico external enclosure and install the drive yourself. That is what I did with my recent purchase of two Samsung 512 gig SSDs. They are fast! And I will be taking one of them when we go to London next month, so that I can watch videos (TV series and/or movies) on the flights back and forth.

For standard HDDs, ones manufactured by Seagate are the best. I would definitely recommend getting one for which the drive spins at 7200 rpm. 5400 rpm is just too slow.

My hard drive in Mac is 500GB, using 450GB.

As for malware hiding inside a video file, it is possible, althoughMac-specific viruses are certainly not as common as ones in the Windows world. Malwarebytes is a good start, but it's not a cure all. This link shows the differences between the 2 versions of that software:

https://buy.malwarebytes.com/us/?ht...arebytes.com&gclid=CLnWktDN-dECFUuXfgod3sQPLA

Note that for the free trial version, 4 of its features expire after 14 days. If you really want to be sure, you could download and run Sophos:

https://www.google.com/search?q=Sop...69i57j69i59.2855j0j4&sourceid=chrome&ie=UTF-8

Another knowledgeable user here recommended it. I have used it in the past, and it worked fine, as I was having an issue with some "Bitcoin-related" malware, even though I have never used Bitcoins. Hopefully, he'll "chime in" here.

So Sophos worked fine and did not cause any issues? That's good to hear.
You uninstalled it later? Just because you had no need for it, not because it was anyway bad to system?

 

[honestone]

For Sophos, that is correct. It helped me somewhat, although I could never get to the root "cause" of the issue with Bitcoin. In fact, it seemed to be not a virus at all. I subsequently did a clean installation of whatever version of El Capitan I was on, and then recovered all my other "stuff" from my SuperDuper! backup. The issue went away.

Regarding how much space you are using on your internal drive, this could be a good time to do some early "spring cleaning" on that drive. You should go through the stuff on the drive, and see what you can get rid of. An excellent (although "block/graphical"), free program to help you with this is Grand Perspective:

http://grandperspectiv.sourceforge.net/

It is excellent, and even with my "an*l" cleaning procedures I go through often, it still helped me identify some stuff I no longer needed. (I like to run "lean, mean, and clean"!).

Another excellent, free program to use is Onyx:

http://www.titanium.free.fr/onyx.html

That venerable program has been around for quite some time, has always been rock solid, and has had many excellent reviews. I actually depend on it (along with TechTool Pro for more robust disk cleanup/maintenance/repairs, and SuperDuper! for my bootable backups). I suspect your machine could use its permissions repaired, and you can do that for Onyx. Most likely, you'll need to run that Repair Permissions feature of Onyx a few times to get all "applicable" permissions repaired.

Note, though, that there are separate versions of Onyx for each Mac OS. So, you'll need to download the appropriate one.

Now, if you decide to go the SSD route, after doing as much cleanup as you can, that should tell you how large of an SSD to get. If you did nothing at all, then you would need an SSD that is at least 750 gig in size. But, if you can get the space on your internal drive down to 350 gig or less, then a 512 gig SSD should be enough. Of course, even after you do the cleanup, it is best if you keep after it, and get rid of stuff as soon as you no longer need it. Also, the more free space you have on your internal drive, the better. For example, on my Mac Mini, I have a 256 gig Samsung SSD, but I am only using about 79 gig. Similarly, on my Mac Book Air, it has a 252 gig SSD, but again I am only using about 78 gig of space. Besides the performance benefits, having that much free space allows me to download occasional large files. I actually store most of my files on an external drive. That is sufficient for my purposes.

If you do the HDD route, then I suspect you'll need a 1 TB drive. Maybe you can find a 500 gig or 750 gig one, but with all the video stuff going on these days, those could be hard to find. A new 1 TB drive should run about $50 to $60 US.

 

[honestone]

I forgot about one other excellent choice, and our resident expert, Cory Cooper, pointed this out in another discussion forum. You can run the excellent software ClamXav, available from here:

https://www.clamxav.com/

I have also used that one previously (when it was free), and it is very, very good at what it does.