Help i need some suggestion or idea

hi everyone, my teacher at university gives us several projects every month. one of the projects is a compressed file protected by a password. the goal is to try to find out what's in the file. i've tried dictionary attacks, brute force attacks etc.. however, my teacher isn't the type to give us something simple, so i've reanalyzed the file and i know it's been compressed by winrar version 5.0. however, i haven't found a CVE or anything that can help me in my research and my exploit. can anyone guide me or give me any ideas?
Y
You133d ago
Known plaintext attacks if you know even the contents of a single file. Some archiving software used to be vulnerabe to that kind of attacks. You should try to search for "winrar password recovery" or something like that.
NR
Nour Rhm133d ago
unfortunately, the file only contains a jpg image that we have to send him
Y
You133d ago
You can maybe do known plaintext just using the image headers. The magic bytes are always the same, you could probably bruteforce the rest.