He didn't find the password in the clear, he found the private key in the clear. He brute-forced the password.

I assume his reasoning for looking for the private key was similar to: this program creates a new certificate authority and installs it on this computer. In order to do this, it must have all necessary tools for doing so, including the private key it uses to create those certificates, in memory somewhere. Even if that private key is stored encrypted somewhere, it has to exist unencrypted in memory at some point to be used.