Explore an in-depth analysis of MoustachedBouncer, a sophisticated APT group conducting long-term espionage against diplomats. Delve into their advanced techniques, including email-based C&C protocols, C++ modular backdoors, and adversary-in-the-middle (AitM) attacks. Uncover how this group leverages AitM in Belarus to redirect potential targets during captive portal checks, compromising diplomats with a custom malware family called Disco. Examine the evidence suggesting MoustachedBouncer's access to Belarusian ISP backends, potentially using SORM devices for targeted surveillance. Learn about this elusive group's highly advanced capabilities that have allowed them to avoid the spotlight while rivaling infamous APTs like Turla. Gain valuable insights from security researcher Matthieu Faou's 37-minute Black Hat conference presentation on this critical cybersecurity threat.