Securobods warn of wide open backdoor in Netis/Netcore routers

Update Routers sold under the brand Netis by Chinese security vendor Netcore have a hardcoded password that leaves users with a wide-open backdoor that could easily be exploited by attackers, claim researchers.

The backdoor allows cyber-criminals to easily change settings or run arbitrary code on routers, securobods at Trend Micro warn.

The backdoor exists as an open UDP port listening at port 53413, accessible from the internet side of the router. This backdoor is “protected” by a single, hardcoded password located in the router’s firmware. The routers – sold under the Netcore brand in China and as Netis outside of the country – all seem to have the same password, according to Trend Micro, which warns that users cannot modify or disable this backdoor.

The security weakness creates a means for hackers to download hostile code or modify the settings on vulnerable devices in order to carry out so-called man-in-the-middle attacks. The researchers said their network scans had suggested that millions of devices worldwide are potentially vulnerable, as a blog post by Trend Micro explains.

Using ZMap to scan vulnerable routers, we found more than two million IP addresses with the open UDP port. Almost all of these routers are in China, with much smaller numbers in other countries, including but not limited to South Korea, Taiwan, Israel, and the United States.

In addition, the file that contains the user name and password for the router’s web-based administration panel is stored without any encryption, claims Trend. This file can be easily downloaded by hackers, the security firm warns.

El Reg contacted China-based manufacturer Netcore on Tuesday but have yet to receive a response. We'll update this story as and when we hear more.

Short of a fix, Trend recommends replacing vulnerable devices. ®

Update

Since the publication of this story, the affected manufacturer, Netis, says it has released a firmware upgrade designed to plug up this security hole.