Phones using a number of popular versions of the Symbian S60 mobile OS (the Nokia N95, E71 and N76 just to name a few) can be partially disabled by a maliciously coded text.
The attack has been lamely dubbed "The Curse of Silence" and it's pretty simple. Due to a glitch in the way that the S60 messaging client handles text messaging, any message from a sender with a name length of over 32 characters, and a small identifier that flags the message as "Internet Electronic Mail." This combination of otherwise rare circumstances causes the messaging client to silently stop receiving any SMSes until the device undergoes a factory reset.
The exploit is very, very easy to carry out and can damage phones running S60 versions 2.6-3.1, which covers a huge swatch of Nokia's product line. Tobias Engel and the Chaos Computer club, who found the bug, released the details to Nokia a few weeks before passing them on to the public, but as of yet there is no official fix, though our tipster says this third-party program does the trick. Check below for a list of affected phones, and have a look over at the Register for a slightly more in-depth description of the exploit. [Tobias Engel—Thanks, Pauli]
S60 3rd Edition, Feature Pack 1 (S60 3.1):
Nokia E90 Communicator
Nokia N95 8GB
Nokia N81 8GB
Nokia 6124 classic
Nokia 6121 classic
Nokia 6120 classic
Nokia 6110 Navigator
Nokia 5700 XpressMusic
S60 3rd Edition, initial release (S60 3.0):
Nokia N91 8GB
S60 2nd Edition, Feature Pack 3 (S60 2.8):
S60 2nd Edition, Feature Pack 2 (S60 2.6):