I have retrieved some old pictures/videos (mp4, many types of avi) of some old events that I want to keep, the problem is that these files have been sitting in confirmed infected machine for a very long time, and noone ever bothered to check what type of malware it was they just backed up and nuked it. My question now is what should be done with these files?
To clarify the files had been on both windows machines and linux server which have been confirmed to be rooted.
My desktop is running linux so if you suggest any software please make sure its compatible.
@OP I may have TL;DR too much, sorry but hope it helps anyway:
This is what your antivirus software's quarantine was designed for. If you can't trust that you can always 7z the files under high compression with a password(password to keep the idiots from extracting it)
I use the 7zip method all the time, usually, I change the file extensions before zipping like so:
I specifically use 7zip because it is open source and I have faith that it has no buffer overflow exploits.
Additionally to what @shroeder and @Philipp have said you could run them through a Video-Converter. As converters write completely new files that that comply exactly to the format that should eliminate eny off-spec data from the files.