LibPAM and Google Authenticator Setup on Centos 7 allows SSH login with any password

**OS:** Centos 7
**The need:** set up 2-factor authentication for SSH login into my web server
**Solution:** set up Google Authenticator following the instructions in the link below

https://www.howtoforge.com/tutorial/secure-ssh-with-google-authenticator-on-centos-7/

**Problem:** Google Authenticator allows SSH login with any gibberish typed into the password prompt 2 times even if the first gibberish does not match the second. When I uninstall google authenticator anyone that is not already logged in is prevented from login even with the correct local password.

I referred the problem to Google security team as a vulnerability of Google Authenticator but was redirected here.