[ale] OT: Possible SMB exploit?

[HolmquistTW at cadet.com (Holmquist, Thomas W.)]

I've been thinking... When you're on windows, and you connect to a server, it automatically logs in to the server (sends username and password) then if you are denied access, it pops up with username and password box... this makes me think that one could have a malicious computer on a network, and whenever someone clicks on it (in my network) it malicious computer recieves that password... Is this possible, or is there something i'm missing?