Q:

How do i stop OS X from sharing wifi passwords between accounts on same machine?

I have a Macbook Pro that has a few user accounts on it (Mine, my S.O., and a Guest account).  Both mine and my S.O.'s account have passwords required to login to them.  The guest account is the standard OS X guest account without any password required.  I noticed that if i sign into a brand new wifi network on my personal account and then switch accounts to the Guest or my S.O.'s, I am still connected to that wifi network.  This seems very strange and not secure to me.  Is there a way to stop OS X from sharing the wifi network login credentials between user accounts?

A:

OS X is not sharing the passwords to WiFi networks among users. These credentials are stored in the System keychain, with "Passwords" category and "Airport network password" kind. Although other users can connect to a network with credentials stored in this keychain, users without administrative permissions will not be able to access this keychain and read the passwords.
Once you connect to the WiFi network the connection remains regardless of what account is actively using the console at the moment.
The situation you described is equivalent to plugging the Ethernet cable. You connect the Mac to the network and the fact that you'd use another account simultaneously does not cause the network to be disconnected.

