Pro-Ukrainian hackers have claimed responsibility for a large-scale cyberattack on Aeroflot on Monday, alleging they have destroyed the Russian airline’s internal IT infrastructure and brought operations to a halt.Aeroflot has confirmed major technical issues but has not disclosed the full extent of the damage. The airline has canceled or delayed over 100 flights, with routes across Russia and several international destinations affected.The hacker groups Silent Crow and Cyberpartisans BY have claimed they were inside Aeroflot’s corporate network for over a year. They say they downloaded more than 20 terabytes of data, compromised all critical systems, and accessed employee computers, including those of top managers. They also claim to have destroyed around 7,000 physical and virtual servers.In a statement, the hackers estimated that restoration could cost tens of millions of dollars and called the damage “strategic.” Following their announcement, Aeroflot warned passengers of internal technical issues and said flight schedule changes were likely. Later in the day, the company announced it had canceled 49 pairs of flights from Moscow, including to Minsk, Yerevan, and Astana. Flights operated by Rossiya and the low-cost airline Pobeda have also been affected.The attack has caused significant disruption at Russian airports. At Sheremetyevo, where Aeroflot is based, large crowds formed as hundreds of passengers sought updates. The company urged people not to come to the airport unless necessary and said rebooking is currently available only to limited categories of passengers. Russia’s Prosecutor General’s Office has confirmed that Aeroflot suffered a hack attack and announced a criminal case.The Kremlin has called the situation alarming. “The hacker threat remains for all large companies providing services to the public,” spokesman Dmitry Peskov said.The attack comes as Moscow airports have already faced months of disruption due to Ukrainian drone activity, which has repeatedly forced temporary flight suspensions.