The websites oftwo bankswere also taken offline.
Those attacks defaced government websites and planted destructivemalwareon Ukrainian computer networks.
Russia has said it’s pulled back some of its troops, a claim NATO says isn’t true.
On Thursday,President Joe Biden warnedthat Russia could still invade Ukraine within days.
The recent cyberattacks fall into a legal gray area as to what constitutes warfare.
Such attacks can cause widespread destruction and are potentially deadly if they close hospitals and nursing homes.
They’ve been on the rise for years and often go unpunished.
The US and its NATO allies are boosting their collective defenses in cyberspace, he added.
There are any number of acts one country could take against another to cause chaos, Hodgson said.
“There is a certain value in not being sure where that line is,” Hodgson said.
Instead, he said, it’s better to look at the impact of a given attack.
Even then, the legal gray zone can make deciding whether to respond tough.
Defacing government websites wouldn’t qualify, for example.
But unleashing destructive malware, like theNotPetya attack in 2017, might fall into that category.
NotPetya, which has been blamed on Russia, disguised destructive malware as more-common ransomware.
Labeling a cyberattack an act of war comes with its own dangers, Meyers said.
Such a response doesn’t necessarily have to be another cyberattack, he added.
It could be a drone strike or economic sanctions.
Cyberattacks shouldn’t be considered separate from warfare, he said.
They’re now a component of statecraft.
Attributing an attack can be tough.
“They take advantage of the ambiguity.
They create ambiguity,” Sorensen said.
That might be something some US companies need to worry about.
