Sergey Puzankov, Lead Security Researcher, Positive Technologies. Sergey has been working in telecom industry for more than 18 years. As the Lead Security Researcher at Positive Technologies, he researches mobile operator security on the part of signaling networks. Sergey conducted research of by-design vulnerabilities in SS7 networks, discovered a number of critical vulnerabilities in mobile network equipment, and showed how an intruder is able to bypass mobile operators' protection means. Author of many articles on telecom security. Sergey is also the general developer of the PT Telecom Vulnerability Scanner tool, member of the PT Telecom Attack Discovery development team, writes Positive Technologies annual analytical reports. Apart from that, Sergey actively contributes discovered vulnerabilities and the results of security researches to global organizations, such as GSMA and ITU, and shares knowledge with the telecom security community. Sergey has given talks at many conferences, such as DEFCON, Hack.Lu, HackInParis, LeHACK, HitCon Pacific, XCON, PHDays, and BSides.