A few things to clarify
The trick only works if developer mode is enabled on the Chromebook. The good thing is, if it's not already in developer mode, we'll show you how to do it. But Enable It will clean your Chromebook with a power wash that means all your profiles, saved files, and even Wi-Fi password will be erased.
This means that you can only get Wi-Fi passwords from the network you connect to after putting the Chromebook in developer mode.
Boot Chromebook into developer mode
To get started, you need to press the Esc, Refresh, and Power buttons on your Chromebook. Pressing these keys together will boot it into recovery mode and give you a message like Chrome OS is missing and insert a recovery stick to restore. No need to worry, the Chrome OS is where it should be, and you'll need to press Ctrl + D to enable developer mode.
There is nothing to fear here. Just press Ctrl+D and continue.
Last chance! If you want to continue, press Enter.
The Chromebook emits a few beeps, then automatically resumes. There is nothing to do here.
Deleting and enabling developer mode can take 10-20 minutes.
Still waiting….
Find the saved WiFi password
Now that your Chromebook is in Dev mode, you can get the password of any Wi-Fi network you connect to. First, connect to the Wi-Fi network you want to crack the password for, then press Ctrl+Alt+T on the Chromebook keyboard. This will open the crosh shell.
Once you see the black shell screen, enter the following codes:
crush > shell
chronos@localhost / $ sudo su
localhost / # cd /home/root/
localhost root # ls
Here you will get the list of a folder with a long string. Just type CD and a tab, then press Enter. You will be directed to the directory. For example
localhost root # cd 6ac138e6f72d5b28ee8d9a344ada72f2f981818a/
localhost 6ac138e6f72d5b28ee8d9a344ada72f2f981818a #
Finally, type the command "more shill/shill.profile" and press Enter. You'll see a line of text with the Wi-Fi information of the networks you've previously connected to.
Locate the Wi-Fi SSID you want to get the password for and discover the line "Passphrase=rot47:" followed by some random text. Well, that's the WiFi password, but it's encrypted. To decrypt, type echo | . a tr '!-~' 'P-~!-O'. Replace the desired code that you receive as a passphrase.
That's all, you have the Wi-Fi password on the screen.
Conclusion
I understand the process is a bit too technical, but you can bookmark this page or save the commands to your favorite notes app. If you need it, you can always go back and even copy and paste the entire commands. If in doubt, please ask your questions in our forum.