In this talk, Kaileigh McCrea from Confiant delves into the incident from late January 2023, where a staggering 45 GB of source code from the Russian search giant Yandex was leaked on BreachForums by a former Yandex employee. Although the leak did not contain user data, it reportedly encompassed the source code for all major Yandex services. This includes Metrika, a service that gathers user analytics through a widely used SDK, and Crypta, Yandex’s behavioral analytics technology. There has been a lot of speculation about what Yandex could potentially do with the vast amounts of data it collects. However, this is the first time outsiders have had the opportunity to confirm it. What we’ve discovered is both fascinating and deeply unsettling.