Cisco confirmed it is possible to eavesdrop on remote conversations using Cisco VoIP phones.In its security response, Cisco says: "an attacker with valid Extension Mobility authentication credentials could cause a Cisco Unified IP Phone configured to use the Extension Mobility feature to transmit or receive a Real-Time Transport Protocol (RTP) audio stream."
Cisco adds that Extension Mobility authentication credentials are not tied to individual IP phones and that "any Extension Mobility account configured on an IP phone's Cisco Unified Communications Manager/CallManager (CUCM) server can be used to perform an eavesdropping attack." (more)
