In my last post, I introduced Microsoft Workplace Join. It’s a really convenient feature that can automatically log users in to corporate accounts from any devices of their choosing. However, this approach essentially eliminates all sense of security.
So, if you’re a sane and rational security professional (or even if you’re not), you clearly want to disable this feature immediately. Your options?
Option #1 (Most Secure, Most Convenient): Completely disable InTune Mobile Device Management for O365 and then disable Workplace Join
Contact Bitglass and replace InTune with the easier-to-deploy, user-privacy-preserving, Agentless MDM alternative.
Option #2 (Least Convenient): Use InTune policies to block all personal devices
Microsoft does not provide a method of limiting this feature that does not utilize InTune policies. Effectively, you must either not use InTune at all, or pay to block unwanted access. However, the latter approach means blocking all BYO devices (reducing employee flexibility and efficiency) and introduces the complexity of downloading software to every device, raising additional costs.
Option #3 (Least Convenient and Least Secure): Whack-a-mole manual policing of new device registrations
As an administrator in Azure AD, deleting or disabling an account only prevents automated logins on each of that account's registered devices - this has to be done manually every time a user links a new endpoint. Unfortunately, deactivation and deletion in Azure do not remove the "Join Workplace or School" link from the control panel of the machine in question. Additionally, deactivation still allows the user to manually log in, as does deletion - neither action prevents the user from re-enrolling the same device. In other words, pursuing this route means playing an endless game of deactivation and deletion whack-a-mole.
If you’d like help with Workplace Join or any other security threat, be sure to contact Bitglass, the Next-Gen CASB.