Russian national flag carrier Aeroflot (AFLT.MM) was forced to cancel dozens of flights on Monday, disrupting travel across the world's biggest country, as two pro-Ukraine hacking groups claimed to have inflicted a crippling cyberattack.
The Kremlin said the situation was worrying, and lawmakers called it a wake-up call for Russia. Prosecutors confirmed the disruption was caused by a hack and opened a criminal investigation.
Senior lawmaker Anton Gorelkin said Russia was under digital attack.
"We must not forget that the war against our country is being waged on all fronts, including the digital one. And I do not rule out that the ‘hacktivists’ who claimed responsibility for the incident are in the service of unfriendly states," Gorelkin said in a statement.
Another member of parliament, Anton Nemkin, said investigators must identify not only the attackers but "those who allowed systemic failures in protection".
Aeroflot did not say how long the problems would take to resolve, but departure boards at Moscow's Sheremetyevo Airport turned red as flights were cancelled at a time when many Russians take their holidays.
The company's shares were down by 3.9% by 1300 GMT, underperforming the wider market, which was 1.4% lower.
A statement purporting to be from a hacking group called Silent Crow said it had carried out the operation together with Belarusian Cyberpartisans, a self-styled hacktivist group that opposes president Alexander Lukashenko and says it wants to liberate Belarus from dictatorship.
"Glory to Ukraine! Long live Belarus!" said the statement in the name of Silent Crow.
Belarusian Cyberpartisans said on its website: "We are helping Ukrainians in their fight with the occupier, carrying out a cyber strike on Aeroflot and paralysing the largest airline in Russia."
There was no immediate comment from Ukraine.
Silent Crow has previously claimed responsibility for attacks this year on a Russian real estate database, a state telecoms company, a large insurance firm, the Moscow government's IT department and the Russian office of South Korean carmaker KIA. Some of those resulted in big data leaks.
"The information that we are reading in the public domain is quite alarming. The hacker threat is a threat that remains for all large companies providing services to the population," Kremlin spokesman Dmitry Peskov said.
Aeroflot said it had cancelled more than 40 flights - mostly within Russia but also including routes to the Belarusian capital Minsk and the Armenian capital Yerevan - after reporting a failure in its information systems. An online departure board for Sheremetyevo airport showed dozens of others were delayed.
"Specialists are currently working to minimise the impact on the flight schedule and to restore normal service operations," Aeroflot said.
The statements from Silent Crow and Belarusian Cyberpartisans said the cyberattack was the result of a year-long operation which had deeply penetrated Aeroflot's network, destroyed 7,000 servers and gained control over the personal computers of employees, including senior managers.
They published screenshots of file directories purportedly from inside Aeroflot's network and threatened to soon start releasing "the personal data of all Russians who have ever flown Aeroflot", as well as intercepted conversations and emails of Aeroflot staff.
ANGRY PASSENGERS
Since Moscow launched its war in Ukraine in February 2022, travellers in Russia have become used to flight disruptions, usually caused by temporary airport closures during drone attacks.
Russian companies and government websites have been subjected to sporadic hacking attacks, but Monday's was potentially the most damaging, because of the widespread disruption and the high profile of Aeroflot.
Former Aeroflot pilot and aviation expert Andrei Litvinov told Reuters: "This is a serious disaster. Okay, flight delays - you can survive that. But these are losses, huge losses for a state-owned company."
He added: "If all the correspondence, all the corporate data is exposed - this can have very long-term consequences ... First the drones, and now they are blowing up this situation from the inside."
Passengers vented their anger on social network VK, complaining about a lack of clear information from the airline.
Malena Ashi wrote: "I've been sitting at Volgograd airport since 3:30!!!!! The flight has been rescheduled for the third time!!!!!! This time it was rescheduled for approximately 14:50, and it was supposed to depart at 5:00!!!"
Another woman, Yulia Pakhota, posted: "The call centre is unavailable, the website is unavailable, the app is unavailable.
"How can I return a ticket or exchange it for the next flight, as Aeroflot suggests?"
Aeroflot said affected passengers could get a refund or rebook as soon as its systems were back and it was trying to get some passengers seats on other airlines.
Despite Western sanctions on Russia that have drastically limited travel and routes, Aeroflot remains among the top 20 airlines worldwide by passenger numbers, which last year hit 55.3 million people, according to its website.
