According to reports, websites of the Ukrainian Cabinet of Ministers, and those of the ministries of foreign affairs, infrastructure, education and others, experienced disruption even as Russia's bombing raids continue.
Key Ukrainian government websites were reportedly down early on Thursday even as Russian President Vladimir Putin announced a special military operation aimed at demilitarisation and denazification of Ukraine.
According to reports, websites of the Ukrainian Cabinet of Ministers, and those of the ministries of foreign affairs, infrastructure, education and others, experienced disruption even as Russia's bombing raids continue.
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In what can pose serious threats to Ukraine's cyber security, a data-wiping tool was reportedly found on hundreds of computers in the country, sparking concerns that a destructive cyberattack was unfolding amid Russia's military offensive.
The incident represents an apparent escalation in cyberattacks on Ukraine's infrastructure, even as the United States, UN, NATO and other allies decried blatant violation of international law and threatening economic sanctions.
The Russian President called on the Ukraine military to 'lay down its arms' in a televised address. Putin said that his country was left no chance to protect itself by other means. "I have decided to conduct a special military operation," he announced.
He also vowed retaliation against those who interfered with the Russian Ukraine operation. "To anyone who would consider interfering from outside. If you intervene, you will face consequences they have never seen. The relevant decisions have been taken. I hope you are hearing me," he said.
Charles Carmakal, senior Vice President and Chief Technology Officer for Cybersecurity firm Mandiant, was quoted by CNN as saying, "We are aware of multiple commercial and government organisations in Ukraine impacted by the destructive malware today."
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The reported hacking incidents came as UN Secretary-General António Guterres made an eleventh-hour appeal to Russia to curtail military action.
"President Putin, in the name of humanity, brings your troops back to Russia," Guterres said after the emergency meeting of the United Nations Security Council convened as a frantic effort to de-escalate the tensions between the two nations.
The consequences of a war would be devastating for Ukraine and far-reaching for the global economy, Guterres added.
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Earlier, US officials had warned of the possibility of Russia using cyber operations in coordination with military action in Ukraine. Last month, President Joe Biden had said that the United States could respond with cyber operations of its own if Moscow launches cyberattacks on Ukraine.
According to reports, a cyberattack on Wednesday temporarily knocked the websites of the Ukrainian Parliament, Security Service and Cabinet of Minister offline. It remains unclear who was responsible for Wednesday's hacking incident or the destructive cyberattacks early today.
Ukraine's State Service of Special Communications and Information Protection earlier said Wednesday's hack was "a continuation" of cyberattacks that hit Ukrainian government websites on February 15.
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Meanwhile, the White House blamed Russia's military intelligence agency, the GRU, for the cyberattacks, which are being called distribute denial of service (DDoS) attacks as they overwhelm computer servers with phoney traffic and knock websites offline. Russia's embassy in Washington denied the accusation.
The destructive data-wiping tool, known as 'wiper' malware, has the potential to be the most impactful, as it deletes data from computers and renders them inoperable. Experts suggest the malware can hobble organisations trying to stay online even as Russian aggression escalates.
Vikram Thakur, Technical Director at Broadcom's cybersecurity unit, told CNN, "The hack hit at least one Ukrainian financial institution and two Ukrainian government contractors, one with a presence in Latvia and the other with a presence in Lithuania."
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According to cybersecurity firm ESET, the malicious code has affected 'large organisations' in Ukraine. "The hacking tool appears to have been created two months ago but was deployed only today, and we have seen it only in Ukraine," Jean-Ian Boutin, head of threat research ESET, told CNN.
On Tuesday, a senior Department of US Homeland Security told local officials that in a military operation between Russia and Ukraine, transportation networks and broadcast media in Ukraine could be shut down by kinetic or cyberattacks.
The US and numerous allied governments and private sector experts are reportedly providing cybersecurity support to Ukraine on the ground and remotely. Senator Mark Warner, the Virginia Democrat who chairs the Senate Intelligence Committee, told CNN that with a top-tier cyber power like Russia, one will not be able to keep them out 100 per cent, so the goal is resilience.
When asked if Washington would conduct its hacking operations in response to Moscow's activities in Ukraine, Warner responded that the US usually avoids 'opening Pandora's Box in terms of cyber escalation'.
"So far, that's been the right approach. But we've never seen this sort of circumstance where Putin is willing to unleash 190,000 troops" and threaten Kyiv. We don't know what he'll do in the cyber realm," Warner told CNN.