The Research in Motion BlackBerry 7270 before 4.0 SP1 Bundle 108 does not properly manage transaction states, which allows remote attackers…

The Research in Motion BlackBerry 7270 before 4.0 SP1 Bundle 108 does not properly manage transaction states, which allows remote attackers to cause a denial of service (temporary device hang) by sending a certain SIP INVITE message, but not providing an ACK when the call is answered.