Have you tried rebooting? Maybe the clipboard has got messed up.
Suspicious though that is a malware site. But it has windows malware. Do you have windows xp open in vmware maybe? heh.
I just noticed something very odd.. no matter what I highlight/copy on my mac: the same thing pastes...
"http://xp-vista-update.net/?id=91873534231" (I wouldn't recommend clicking this.)
At first I thought this was a glitch and a restart would fix it, but then I thought about why I would ever have copied this link (being a Mac user), the fact that it appears to link to a Windows update site (which is often the guise of an attacker), and that a little bit ago I was interrupted while Digg-browsing by an 'onslaught' of popups that resulted in downloading/launching two disk images!
So, now I think I may have a virus on my mac. I checkted McCaffee's SiteAdvisor and they list "xp-vista-update.net" as safe, but it's another popup farm. My idea now is that this is either a virus caused by something downloaded (but not the disk images since I never installed their contents), or a loop-hole exploit where a very unmalicious hacker is having my browser accept code (java or flash) that messes with the copy controls or clipboard. I only think that because of the popups and the fact that I'm on a mac and it's linking to a windows-user-targeted site (so maybe it's browser related and therefore operating system independent). Since it's so unmalicious, could it just be proof of concept?
Either way, it makes me think twice about never putting any special antivirus or security software on my mac.
Does anybody have this issue?
Alex

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