Our school has tightened up.
A kid hacked the computer last year and set the wallpapers of all the computers as porn. Very clever exploit, he made a batch file for scheduling a task to set the wallpaper and a few other things, and ran it on a couple computers with some kid's password he got. So when he ran it, it would affect that computer, but then whoever logged onto that computer it would affect. And then when that user went onto another computer, it would spread to that one, and so on.
We've got Deep Freeze on them now though, so every time a user logs off, it wipes the hard drive to a set state. Makes it difficult to exploit it, although I've found my methods...(HijackThis is good at killing tasks!)
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