The Liberia Telecommunication Authority (LTA) has denied reports that the country’s internet access has been disrupted by a large-scale hack attack.
The LTA said there was “no data to substantiate” the claim but admitted that one telecommunications company serving half the nation’s mobile users did suffer attacks that repeatedly limited access.
Security experts who monitor networks of hijacked devices used to carry out attacks, called botnets, noticed last week that Liberian net addresses were among targets being deluged with data.
Media reports quoted network security firms outside the country and telecoms staff in Liberia who said internet access in the country was affected.
The attacks were mounted using the massive Mirai botnet that in late October was used to cause the web-wide disruption that left Reddit, Spotify, Twitter and other popular sites hard to reach.
Jarsea Burphy, a spokesperson for the Liberia Telecommunication Authority, said monitoring systems on the nation’s internet exchange point, where domestic traffic joins the global network, showed no evidence that the link had been overwhelmed.
The monitoring systems showed “no downtime in the last three weeks,” she told the BBC.
Ms Burphy said a single local operator, believed to be the Lonestar Cell mobile network, had been subjected to intermittent web attacks that had affected its ability to provide net access.
Lonestar, which has a 50 percent market share, said in a release in Monrovia, that it had been hit by so-called Distributed Denial of Service attacks that sought to overwhelm its network.
“We have continued to react and restore service to each incident as it happens,” it said.
Liberia has been repeatedly cut off from the internet by hackers targeting its only link to the global network.
Recurrent attacks up to November 3 flooded the cable link with data, making net access intermittent.
Researchers said the attacks showed hackers trying different ways to use massive networks of hijacked machines to overwhelm high-value targets.
Experts said Liberia was attacked by the same group that caused web-wide disruption on October 21.
Those attacks were among the biggest ever seen and made it hard to reach big web firms such as Twitter, Spotify and Reddit.
The attacks were the first to send overwhelming amounts of data from weakly protected devices, such as webcams and digital video recorders that had been enrolled into what is known as a botnet.
A botnet variant called Mirai was identified by security firms as being the tool used to find and compromise the insecure devices.
The source code for Mirai has been widely shared and many malicious hacker groups have used it to seek out vulnerable devices they can take over and use to mount what are known as Distributed Denial of Service attacks.
“There’re multiple different botnets, each with a different owner,” security researcher Kevin Beaumont told the BBC. “Many are very low-skilled. Some are much better.”