The Nokia 6310, 6310i, 8910 and 8910i phones can be attacked with a technique known as "bluesnarfing", which allows a hacker to access, and in some cases modify, data such as the address book and calendar. The 6310i may also suffer a denial of service if it receives a specially crafted Bluetooth message.
UK-based A.L.Digital discovered the flaws at the end of last year, also indicating similar flaws in Sony Ericsson devices. The firm has yet to confirm or deny the claims.