Twitter all clear after worm wave

Twitter has been given the all clear after a worm infected "tens of thousands of users". But experts say the attack could have been much worse. Over the weekend, a self-replicating computer program, or worm, began to infect profiles on the social network. The worm was set up to promote a #Twitter rival site, showing unwanted messages on infected user accounts. Michael Mooney, a 17-year-old US student, told the Associated Press he created the worm to promote his site - BBC