Hijacked browsers. Is "spi" Spigot?

All of my browsers (Safari, Chrome, Firefox) have been hijacked. A Google search shows the Google results for less than a second, then it switches to a Yahoo page that does not show the actual search results, it shows only things that if clicked on, will presumably pay the owner of the the trojan horse. It renders search useless. Happens on Bing and Yahoo also.

I've had this before and it was called Spigot, which was easy to get rid of. This one appears to be "spi." I get messages from Little Snitch asking if I want to "allow spi to change configurations." and other messages. Is this spi legit or is it part of the scam?

Any ideas how to get rid of it?