When Queues Become Vulnerabilities: Reverse Engineering GCD, XPC Races, and macOS Detection

How do seemingly harmless queues become security vulnerabilities?

In this Black Hat USA 2026 session, Olivia Gallucci explores the intersection of reverse engineering, macOS internals, and detection engineering, diving into how Grand Central Dispatch (GCD) and XPC race conditions can introduce unexpected security risks. Through a detailed examination of queueing mechanisms and asynchronous system behavior, the presentation highlights techniques for identifying, analyzing, and detecting vulnerabilities that emerge from complex interactions within macOS.

Whether you’re a reverse engineer, threat hunter, detection engineer, or macOS security researcher, this session offers valuable insights into uncovering race conditions, understanding their security implications, and building more effective detection strategies.

Olivia Gallucci | Security Engineer, DatadogBlack HatRead More