I have a couple questions about malware and exploits that I hope someone could answer to help me better understand those topics.
First: I know of two dominant ways to spread malware. The malware can be in an executable file and cause an infection when the user runs the file. Or the malware can be embedded in some other file type (image, video, ...) that uses a specific application to open the file. From there, a security vulnerability in that application can be exploited to cause the infection. Both of these methods require the user to use the infected file. My question is (and I can't believe I couldn't find the answer anywhere):
Can your computer become infected from the mere act of downloading an infected file (without running it)? I suppose another way of asking this might be, "Can a file be programmed to start itself upon downloading?"
Second: Can a file in an archived format (zip or rar or whatever) be made to execute as soon as it is extracted? Or is it safe to extract files from an archive before running a virus scan on them? And for that matter, do virus scanners work correctly on archived files?
And finally: If you convert an infected video file to a different container format before playing it, is it possible for the malicious code to survive the conversion?
This wound up being pretty long winded but thanks for reading. Any help at all is appreciated! Thanks!