DrayTek routers are affected by a zero-day vulnerability that could be exploited by attackers to change DNS settings on some models.

Routers manufactured by vendor DrayTek are affected by a zero-day vulnerability that could be exploited by attackers to change DNS settings on some of its routers.

DrayTek confirmed to be aware that hackers are attempting to exploit the zero-day vulnerability to compromise its routers.

Many users reported on Twitter cyber attacks against its routers, in these cases, hackers have changed DNS settings of the routers to point to a server having the IP address on the network of China Telecom.

It is likely attackers are conducting a Man-in-the-Middle attack to redirect users to bogus clones of legitimate sites to steal their credentials.

Draytek Dns

DrayTek published a security advisory warning of the attacks providing instructions on how to check and correct DNS settings.

“In May 2018, we became aware of new attacks against web-enabled devices, which includes DrayTek routers. The recent attacks have attempted to change DNS settings of routers.” reads the security advisory

” If you have a router supporting multiple LAN subnets, check settings for each subnet.  Your DNS settings should be either blank, set to the correct DNS server addresses from your ISP or DNS server addresses of a server which you have deliberately set (e.g. Google A known rogue DNS server is – if you see that, your router has been changed.  “

The company is already working on a firmware updates to patch the issue.

DrayTek published a second advisory that includes the list of devices and firmware versions that it is going to release in the coming days.

Initially, the company suspected that victims of the attacks were using DrayTek routers with default credentials, but one of them clarified that its device wasn’t using factory settings, a circumstance that confirms that attackers are in possession of a zero-day exploit.

Searching for DrayTek routers online with Shodan we can find more than 800,000 connected devices connected online, some of them could be potentially compromised with the mysterious exploit.


As a security precaution we have patched all of our customers DrayTek routers and added each device into our Firewall console. If you'd like information or would like us to add your DrayTek into our Firewall console, call us now.