Grad student demonstrates how phones can be turned into listening devicesSubmitted by Ed Thinking on Mon, 12/17/2012 - 16:08
A researcher has demonstrated how Cisco Voice-over-IP (VoIP) phones can be hijacked and turned into listening devices.
At the Amphion Forum this month, Columbia University grad student Ang Cui demonstrated how networked printers and phones can be abused by attackers. The forum, held in San Francisco, is produced by Mocana, which makes security software for non-PC devices that connect to the Internet.
"The attack I demonstrated is caused by the multiple vulnerabilities within the syscall interface of the CNU [Cisco Native Unix] kernel," Cui tells Dark Reading. "It is caused by the lack of input validation at the syscall interface, which allows arbitrary modification of kernel memory from userland, as well as arbitrary code execution within the kernel. This, in turn, allows the attacker to become root, gain control over the DSP [Digital Signal Processor], buttons, and LEDs on the phone. The attack I demonstrated patches the existing kernel and DSP in order to carry out stealthy mic exfiltration."
As part of the demonstration, Cui inserted and removed a small external circuit board from the phone's Ethernet port -- a move he asserted could be accomplished by someone left alone inside a corporate office for a few seconds. He then used his own smartphone to capture every word spoken near the VoIP phone, even though it was still "on-hook."