Apparently, the AdminCP's login interface is accessible. After punching in the login credentials, the XenForo logo will run through the AutoLoader process before throwing me back to the login interface again.
In order to break out of this cycle, I have to disable the APC cache option in the config.php file. I have tried to use the apc.filter variable to exclude out the AdminCP file but to no avail.
Is there anything that I may have missed out on?