“Multifactor authentication will keep the bad guys out” is the hue and cry of hardeners everywhere, so what is the pentester to do? This talk will present a variety of practical attacks against multifactor authentication, ranging from basic configuration oversights to attack strategies that might work forever even if they configure it right. Multiple technologies will be presented. Many people trust their MFA implicitly, as if it’s a magic talisman of keeping hackers out, but there is much a pen-tester can do (and thus, much the other kind of hacker can do), and it’s important to discuss and illustrate the risks. This talk should be useful for you if you’re a pen- tester, but also if you are a defender trying to get the most out of your MFA.