VOIP Phreakers Exploit Billing Hole
Industry sources have confirmed that a new generation of "phreakers" may be able to manipulate data switched through a hybrid TDM-VOIP network, allowing them to make free calls.
Industry executives confirmed that the hack was in the wild, although they could not provide estimates of how serious the exploit was. News of the exploit was originally published by the Broadband Business Forecast, a subscription newsletter for the broadband industry. According to the BBW and industry executives, pure VOIP networks can not be exploited by the hack, which requires a VOIP network passing through an older TDM-based (Time Domain Multiplexing) switch and billing system. The hack involves fooling the system into thinking that the call was disconnected, when in reality the call actually continues. Billing agency software monitoring the call reads it as a disconnect or a dialed call, and does not charge the dialing number.
"As people become familiar with VOIP the ability to commit fraud will become very significant," said Shawn Lewis, chief technical officer of VOIP Inc., a provider of IP customer premise equipment and services. Lewis said he had seen evidence of the exploit, but could not provide estimates of how prevalent it is.
