Learn about physical access control system vulnerabilities in this 17-minute conference talk from DEF CON 32. Explore various exploitation methods targeting credentials, communication protocols, hardware, and firmware, with a special focus on how multiple weaknesses can be combined for more effective attacks. Discover both simple exploits requiring minimal expertise and more complex attacks demanding deeper technical understanding. Gain insights into the importance of mutual authentication verification in physical access control systems through interactive demonstrations featuring HID readers, hardware, proxmark3, and flipper zero devices. Master practical mitigation strategies to enhance facility security and protect against these potential threats.