Our main motto of this session is to walk through the multiple vulnerabilities present in PBX that may possess threat to any individual or organization. This talk will demonstrate multiple exploitable security vulnerabilities including impact, attack scenario and mitigations that we came across while playing with different PBX. Hackers could explore the vulnerabilities to launch various security attacks and security professionals will learn how to mitigate against them. Our presentation will not be limited to the one, but many PBX vendors.