Threat looms of Russian attack on undersea cables to shut down West’s internet

“Based on evolving intelligence, Russia might be planning a cyber attack against us,” Biden said at a press conference on March 21. “The magnitude of Russia’s cyber capacity is fairly consequential and it’s coming.”

Biden added that “one of the tools (Russia’s) most likely to use, in my view – in our view ­– is cyber attacks. They have a very sophisticated cyber capability”.

This is not the first time since the start of Russia’s invasion of Ukraine that the US president has warned about the threat of such attacks. The day after the launch of the Russian invasion on February 24, Washington announced it was “prepared” to ward off any Russian cyber attack.

Biden urged American companies to “lock their digital doors” as quickly as possible to protect themselves. The fear is that “unprecedented cost inflicted on Russia” by all the latest international sanctions could push Russian President Vladimir Putin to retaliate by directly attacking NATO countries using cyber weapons, Biden said.

Moscow was quick to categorically reject these accusations. “The Russian Federation, unlike many Western countries, including the United States, does not engage in state-level banditry,” said Kremlin spokesman Dmitry Peskov on Tuesday.

More than 430 underwater cables at risk

But Biden’s warnings have nonetheless revived the spectre of a digital disaster scenario where Russia would deprive the whole world of the internet by attacking the web’s undersea cables.

This prospect has been raised more than once, even in high military circles, since the beginning of the Ukrainian crisis. In January 2022, Admiral Tony Radakin, head of the British armed forces, said that Moscow could “put at risk and potentially exploit the world’s real information system, which is undersea cables that go all around the world”, reported the Guardian newspaper. Radakin’s theory was shared by the influential American think tank Atlantic Council, which published an article on the risk of the Kremlin severing global internet cables at the beginning of the year.

In excess of 430 undersea internet cables represent tempting targets for anyone wishing to disrupt global connectivity. Often seen as one of the weakest links in the global network, these cables “look like large garden hoses lying at the bottom of the sea”, Tobias Liebetrau, an expert on international relations and IT security issues at the Danish Institute for International Studies, told FRANCE 24.

Above all, they have no special protection, except for “integrated surveillance systems that can send out alerts only if there is a threat nearby”, added Liebetrau.

Easily concealed attacks…

“It is theoretically very easy to conceal the sabotage of an undersea cable,” said Christian Bueger, a specialist in maritime security issues at the University of Copenhagen, speaking with FRANCE 24.

All it would take to damage a cable would be for a merchant ship or fishing boat to drop its anchor on one not far from the coast, where these infrastructures are at a reasonably shallow level. Divers or submarines could also place explosives on the cables or install mines nearby, which could then be detonated remotely.

These operations appear simple, but the results could be potentially spectacular and very costly for Western economies. As soon as a European internet user logs into their Gmail inbox, writes a tweet or “likes” a school friend’s Facebook post, their requests cross the Atlantic via a network of these undersea cables.

“They are vital if you are trying to transfer data to countries overseas,” said Emile Aben, a computer security specialist at the RIPE Network Coordination Centre, an NGO that serves as a regional IP address registry for Europe and the Middle East, speaking with FRANCE 24.

If the hypothesis of a Russian attack against these infrastructures is so worrying, it is because “Russia has been spotted doing naval research or exercises close to places where the cables are located”, said Bueger. Russian ships have carried out exercises near Ireland and Norway, where several submarine cables linking Europe to the United States run. Russian research boats were also spotted in 2014 off the coast of Portugal, again in an area where there are a dozen submarine cables. For years, there has been a suspicion that “Russia is up to something”, noted Bueger.

… but difficult in practice

Bueger explained there is also “the impression that during each conflict, the means of communication are always among the priority targets. During the Second World War, it was the telegraphs, and today it would be the undersea cables”.

The big difference is that depriving the world of the internet is not as easy as it was to cut electric wires on the front line in 1939. “Attacking one internet cable is a bit like destroying a single lane on a ten-lane highway. If the highway has enough capacity, traffic won’t notice,” said Aben. Highly connected countries, such as most European states, the United States or Asian countries, rely on much more than one cable to link them to the world precisely because these infrastructures are so vulnerable.

“Apart from a few isolated islands, there are very few countries that would be deprived of the internet if only two or three cables were damaged,” said Liebetrau. The islands that would be affected include the Azores archipelago, the island of Madeira and the Australian state of Tasmania.

“Russia would have to mount a large-scale military operation to really threaten internet access for targets like the United States or Europe,” said Liebetrau. “They would need to do a lot of reconnaissance operations to find out exactly where each cable is located, because although maps exist, they are deliberately not very precise”.

Russia would then have to mobilise a large number of ships and submarines to strike all the targeted cables simultaneously. “One place to target would be the Suez canal because it’s a choke point for data transfer between Europe and Asia. But you would need to use explosives,” said Bueger.

Moreover, this kind of action would mainly target the civilian population. “While there is no alternative to undersea cables for everyday internet use [managing financial flows, watching movies, playing video games], some less data-intensive communications, such as military or government-to-government communications, could still be handled by satellite networks,” said Bueger.

This is why, even if in theory undersea cables appear to be prime targets, “it’s highly unlikely that Russia would go down this route”, reassured Liebetrau. An attack of this level would be considered an act of war by the West, as confirmed by Radakin. And Moscow would probably not be willing to escalate such an operation, which would require a lot of resources without having any significant impact on NATO’s military capabilities.

It is possible, though, that Russia could make some lesser level of attack, just to prove their power. “I can see them going after one or two cables as a symbolic gesture,” agreed Bueger.  “It would fit the pattern of Russia using their new weapons, because it would be an advanced type of attack.”

This article has been translated from the original in French.