PAM, or Pluggable Authentication Module, is available as an addon for MineOS-node. This feature is enabled by default on MineOS-python.
Using PAM requires installing it as a package on your distro and then building the npm module manually.
apt-get install libpam0g-dev
Build the authenticate-pam module
cd /usr/games/minecraft && npm install authenticate-pam
Different distros will require a different first step based on the package manager, but the second step will be the same in all cases. Note, you will need to rebuild authenticate-pam manually if you use the reset_webui.sh script.