Although it apparently causes no actual harm besides a trivial annoyance, a worm that hits jailbroken iPhones has security researches worried. The so-called Ikee worm was discovered by security researchers recently. It installs a picture of pop singer Rick Astley and displays the message “Ikee is never going to give you up” on victims’ iPhones. The concept is based a widespread Internet prank known as “Rickrolling.” However, the worm prevents further reinfection by shutting down the vulnerability it exploited.