Russia’s top oil producer Rosneft said a large-scale cyber attack hit its servers on Tuesday and computer systems at some banks and the main airport in neighboring Ukraine were also disrupted.
A Moscow-based cyber security firm, Group-IB, said it appeared to be a coordinated attack simultaneously targeting victims in Russia and Ukraine.
In Copenhagen, global shipping firm Shipping company A.P. Moller-Maersk said it had suffered a computer system outage caused by a cyber attack thought it was not immediately clear if it was connected.
One of the firms Group-IB said had been hit in Russia, Damco, which is Maersk’s logistics company.
The latest disruptions follow a spate of hacking attempts on state websites in Ukraine in late 2016 and repeated attacks on its power grid that prompted security chiefs to call for improved cyber defenses.
Rosneft, one of the world’s biggest producers of crude oil by volume, said its oil production had not been affected.
“The company’s servers underwent a powerful hacking attack,” the company said on Twitter.
“The hacking attack could lead to serious consequences, but the company has moved to a reserve production processing system and neither oil output nor refining have been stopped.”
Rosneft’s website was unavailable in Moscow as of 13:25 GMT and had been offline for at least an hour before that.