The worm, dubbed Mabir.A, appears to be a variant of the Cabir virus -- recognised by security experts as the first smartphone virus.
Security firm F-Secure reported on Monday that Mabir.A, like Cabir, can spread to another phone with an open Bluetooth connection. In addition, it can also propagate via Multimedia Message Service (MMS) messages, by sending itself as a reply when an infected phone receives an MMS or text message.
This makes Mabir.A the first smartphone virus to use MMS to spread. As with Cabir, a user would first have to agree to accept Mabir.A and then choose to run it on their phone, which limits its ability to spread. However, the virus could be mistaken for a genuine reply as it sends itself in response to MMS and text messages.
Mabir doesn't cause any damage to an infected phone, and it's not clear how widely it has spread. Symbian wasn't able to say it had received any complaints, but suggested that users were more likely to complain to their network operator.
"We'd be the last ones to know if it was in the wild," said a Symbian spokeswoman.
She added that Symbian was analysing Mabir.A internally, and would issue a report in due course.