Here's a way to crack the zip files with passwords. First of all download and install fcrackzip, if you're on a debian based distro the command to run is :

# aptitude install fcrackzip

That's all. Once it's installed you'll have to run the command with few parameters here's some explanation of some options :

-b option will let you select the brute force attack mode. This means that it'll trie all the possibilities.

This is a very interesting project called OpenWrt. It's a GNU/Linux distribution for embedded devices. This wil let you change your modem software and get a new and open firmware that you can use and modify as you want.

The link to the website of the project is : https://openwrt.org/

Happy hacking ;)