When I unlock System preferences, is OS X during this time vulnerable?

[XPcentric]

Just curious if OS X is vulnerable to attacks from the network when I keep unlocked System preferences for some amount of time.

[Intell]

No. The only way it could be vulnerable while it is unlocked is if someone sat down at your machine and changes your settings.

[JordanJ]

As Intell said.

The unlock feature on System Preferences is a local machine feature (i.e. it does not query the web for authorisation). The risk by leaving System Preferences logged in is that someone could change your settings. This could only happen if someone was physically at your machine, entering your machine remotely etc... None of this could happen by leaving System Preferences unlocked.