A group of cryptographers has developed a new attack that has broken Kasumi, the encryption algorithm used to secure traffic on 3G GSM wireless networks. The technique enables them to recover a full key by using a tactic known as a related-key attack, but experts say it is not the end of the world for Kasumi. The paper describing the new attack is not yet public, but the Emergent Chaos blog has a good description of the attack. It comes just a couple of weeks after researchers published a method for attacking the older A5/1 GSM algorithm.
Source: https://threatpost.com/second-gsm-cipher-falls-011110/73353/