Sippts
Set of tools to audit SIP based VoIP Systems
... is a set of tools to audit VoIP servers and devices using SIP protocol. Sipscan is a fast scanner for SIP services that uses multithread. Sipscan can check several IPs and port ranges and it can work over UDP or TCP. Sipexten identifies extensions on a SIP server. Also tells you if the extension line requires authentication or not. Sipexten can check several IPs and port ranges.