No, not a terrorist attack — just simple stupid hacks to redirect people to porn and other junk. Largely used for search engine optimization.
The city of Dinuba, California and Inyocourt seem to have some problems. They’ve got pages on their servers which redirect to porn.
But it’s not only porn. Check out these pages at NASA.
Click one of those links and what you get is this:
Or how about this at a US Bankruptcy court:
Click on one of those links and you get this: