According to a report by Reuters that Kyivstar mobile operator was hit by a cyberattack , resulting in most of the network to be taken down , as quoted by Reuters
KYIV, Dec 12 (Reuters) - Ukraine's biggest mobile network operator said it hoped to restore operations by Wednesday after coming under what appeared to be the largest cyberattack since Russia launched its war on the country in February 2022.
Tuesday's attack on Kyivstar, which has more than half of Ukraine's population as mobile subscribers, knocked out services, damaged IT infrastructure and put millions of people in danger of not receiving alerts of potential Russian air assaults.
It also disrupted the air raid alert systems themselves in parts of Kyiv.
The company's Chief Executive Officer Oleksandr Komarov said the attack was "a result of" the war with Russia.
And a report by Netblocks website shows the attack impact on multiple cities :
"(The attack) significantly damaged (our) infrastructure, limited access, we could not counter it at the virtual level, so we shut down Kyivstar physically to limit the enemy's access."
Komarov did not say which Russian body he believed to be responsible, but said personal data of users had not been compromised.
Russian hacktivist group Killnet claimed responsibility for the attack via a statement on the Telegram messaging app, but did not provide evidence.
A source close to Kyivstar said the Ukrainian military was not affected by the outage.
Ukraine's SBU intelligence agency told Reuters one of the possibilities it was investigating was that of a cyber-attack conducted by Russian security services.
Russia's foreign ministry did not immediately respond to a request for comment.
Kyivstar, which has 24.3 million mobile subscribers, as well as more than 1.1 million home internet subscribers, said late on Tuesday that fixed-line services were partially restored and it was working to restore other services by Wednesday.
"This isn't the first attempt to breach the perimeter of the country's telecom operator, but unfortunately, this attempt has been successful," Komarov told Forbes Ukraine.
Accessing the Kyivstar website would give this message (machine translated from Ukrainian) :