Kerberos S4U and U2U Extensions in Active Directory Security

Explore a 30-minute conference talk from NorthSec that delves into Kerberos extensions within Active Directory, specifically focusing on S4U (Service-for-User) and U2U (User-to-User) mechanisms and their associated attack vectors. Learn about the technical implementation and peculiarities of these protocols, including how they can be exploited and combined in attacks like spn-less-rbcd, unpac-the-hash, and sapphire ticket. Gain deep insights into the sapphire ticket attack, a particularly stealthy variant of the golden ticket attack that poses significant detection challenges. Master the fundamental workings of these protocols to better understand their security implications in Active Directory environments.