Summary
SymbOS/Commwarrior.F is a worm that operates on Symbian Series 60 devices. The worm is capable of spreading both over Bluetooth and MMS messages.
When Commwarrior infects a phone it will start searching for other phones that are within Bluetooth range and send infected SIS files to the found phones. The SIS files that Comwarrior sends are randomly named, so that users cannot be warned to avoid files with any given name. In addition to spreading over Bluetooth, Comwarrior will also read the users' local address book for phone numbers and start sending MMS messages containing the commwarrior SIS file to those numbers.
MMS messages are multimedia messages that can be sent between Symbian phones and other phones that support MMS messaging. As the name implies, MMS messages are intended to contain only media content, such as pictures, audio or video, but they can contain anything, including infected Symbian installation files.