The full restoration of the IT system of Russia's national carrier Aeroflot, which was hit by a massive cyberattack leading to the disruption of over 100 flights, may take up to a year, according to a media report on Tuesday. Aeroflot came under an unprecedented cyberattack by two hacker groups on Monday. “On average, recovery from a large-scale cyberattack can take anywhere from several weeks to six months,” Russian daily Kommersant quoted an information security expert as saying. However, in Aeroflot’s case, the damage appears to be more severe. While the recovery of some of Aeroflot’s IT systems following the massive cyberattack may take up to two months, complete restoration could take as long as one year, the daily reported on Tuesday, citing experts. The large-scale cyber intrusion led to the cancellation of over a hundred flights, forcing the airline to allocate additional resources at Moscow's Sheremetyevo Airport to stabilise its operations. The Russian Office of the Prosecutor General is supervising the criminal investigation into the incident. Two hacker groups -- the Belarus-linked ‘Kiberpartizani BY’ and ‘Silent Crow’, which had earlier leaked personal data of 101,000 individuals in January 2025 -- have claimed responsibility for the cyberattack. The full extent of the damage remains unclear, but analysts warned of not only direct financial losses and infrastructure recovery costs but also the possibility of regulatory sanctions, given Aeroflot’s status as a "strategic state company with critical infrastructure facilities", the report said. Aeroflot had managed to regain partial control of its systems by Monday evening. The airline’s flight to Delhi reportedly departed with a slight delay but arrived at the Indira Gandhi International Airport on time.