Additional Security for ByPass URL like MFA ?

Summary:

We have a few users using bypass URL to login to the environment. As part of our internal security drive, we need to enable MFA for any basic authentication. Are there any options to add an additional layer of security for users using the Bypass URL like multi factor authentication etc ?

Also are there any ways to keep the URL network restricted ? We have seen the URL is easily accessible outside the network as well and this leaves it be exposed.

Please suggest any option or out of box solution.

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