Russian hackers reportedly breached telecom network months before attack

A December cyberattack against Kyivstar—Ukraine's largest telecom—caused widespread service outages for roughly 24 million customers and reportedly involved destructive wiping of thousands of virtual servers and PCs. Ukrainian authorities attribute the intrusion and prolonged access to the Russian military-linked Sandworm group (claims echoed by a persona calling itself Solntsepek), suggesting capabilities to intercept communications and access subscriber data; Kyivstar disputes aspects of the timeline and data-leak assertions while investigations continue.