Entered password, concerned about hacking
Dear all,
When I recently had a messageboard site open, the Software Update dialog box opened (of its own accord) and asked that I enter my user password so that it could make changes. As I have Software Update run automatically, I didn't think much of it, and entered my administrator password -- only to realize that Software Update was in fact not open, and when I opened it manually confirmed that it had last run 48 hours before.
Naturally I'm concerned that someone on the messageboard site had remotely connected to my computer and I had entered my password for him/her. I immediately changed my OS X password and restarted my computer, but about 10 minutes after restarting a "shade" covered my screen and text appeared, in several languages, telling me that my computer needed to be restarted.
I restarted the computer manually and sent an error report to Apple as prompted, but am still extremely worried that someone has access to my computer.
Has anyone had similar experiences? Does anyone know what might be going on (if anything's going on)? Thank you very, very much.
MacBook Pro, Mac OS X (10.6.8)