September 12, 2017 By Mark Samuels 2 min read

Router security fears have prompted a researcher to recommend that members of the general public disconnect their D-Link 850L routers from the internet.

Security researcher Pierre Kim revealed his findings in a blog post. The scale of the problem, which includes 10 zero-day flaws, is significant. Threat actors could potentially use the flaws to gain root access and control routers remotely.

News of the flaw adds to a growing body of evidence surrounding the potential threat posed by router security concerns. Users and IT managers alike must stay alert to this risk and follow Kim’s suggestion to disconnect affected routers from the internet.

What Is the Extent of the Router Security Issue?

Kim said in his blog post that the vulnerabilities were discovered in the D-Link 850L, which is a wireless AC1200 dual-band gigabit cloud router. The technology also allows users to take advantage of Mydlink Cloud Services and to interact with their home networks from a distance.

Both versions of the router, revA and revB, are affected by the flaws. The vulnerabilities are such that Kim said he could compromise everything, including the wireless area network, the local area network and the custom Mydlink cloud protocol, in his test.

The 10 zero-day vulnerabilities cover a range of router security concerns, including firmware protection, administration passwords and backdoor access. Kim reported the details surrounding these concerns — and the potential impact on users — in his blog post.

How Were the Vulnerabilities Discovered?

Kim found the bugs in June, while the advisory note was created in July. The public advisory emerged on security mailing lists recently. He explained, “The D-Link 850L is a router overall badly designed with a lot of vulnerabilities.” He advised members of the public to “immediately disconnect vulnerable routers from the internet.”

The researcher published his results after encountering difficulties in previous exchanges with D-Link. His research was revealed without coordinated disclosure because of what he perceived to be a lack of prior consideration about security at D-Link.

D-Link apparently downplayed the findings and suggested Kim found the issues by chance, reported ZDNet. The publication contacted D-Link but has yet to receive a response, suggesting it will update the story if it hears any additional information.

What Is the Scale of the Problem?

News of the router security issues should raise alarm among members of the public. Security researcher and chairman of the GDI Foundation, Victor Gevers, estimated there are about 95,000 D-Link 850L routers that are potentially exposed, reported Bleeping Computer.

The scale of the problem, including 10 zero-day vulnerabilities, is alarming, as noted by the International Business Times. The publication reported that the U.S. Federal Trade Commission sued D-Link recently, suggesting the manufacturer relied on inadequate security measures that left users vulnerable to hacking.

It is also worth noting that router security has long been viewed as a potential weak point. Late last year, fraudsters claimed to have compromised 3.2 million home routers by pushing a new firmware update that caused the devices to reach out to malicious servers even after being reset.

Other manufacturers have also been affected by router security issues. Cisco announced a critical router vulnerability last year and Ubiquiti Networks issued a security alert in May 2016 as a response to reports that its routers had seen infections performed by a worm. Users and managers should take note of these alerts and should always run firmware updates.

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