There is a problem that has surfaced with Cisco’s IP phone. It turns out that the phones (7940/7960) are susceptible to a denial of service that can happen with as few as 3 specially crafted SIP messages. The affect on the phones is a reboot. Though I’m sure it can be crafted in other ways.
The code for the exploit is available on milw0rm.
There is an upgrade for the firmware available from Cisco.
Tags: Cisco, Cisco IP Phones, SIP Exploit
