What is DNS Sinkhole?

A DNS sinkhole is also commonly known as a sinkhole server, a blackhole DNS, or an internet sinkhole. DNS Sinkholes are a DNS protection strategy that redirects malicious traffic to fake IP addresses where honeypots are sitting for forensic analysis, or simply provide a blocking answer. Cyber Security specialists use this technique to thwart cyberattacks. DNS sinkholes supply a false IP address in response to a DNS query. The purpose of a DNS (Domain Name System) sinkhole is to stop connections potentially being made to any malicious domains.

DNS sinkholes redirect users to an IP address that is completely different from the one they are attempting to reach. This setup is a tool most often used in an attempt to prevent cyber attacks. Usually configured inside DNS recursive servers, DNS sinkholes are simple to execute and a fairly effective cybersecurity strategy.

If the most basic level of cybersecurity (firewalls, proxies, etc.) is penetrated, then DNS sinkholes are the next line of defense against vicious malware or determined hackers. The malicious traffic that is redirected to a dummy IP address will be captured and then thoroughly analyzed by cybersecurity analysts.

In an effort to thwart malicious connections to botnets, DNS sinkholes are regularly used in DNS spoofing, encouraging DNS servers to thwart communications with dangerous domains or URLs.

DNS sinkholes are effective, but they should not be the only technique used as an enhanced cybersecurity measure.

How we do this at EfficientIP

At EfficientIP we offer DNS Firewall and DNS Guardian Client Query Filtering to apply DNS filtering rules and either block recursion traffic or push client traffic to a specific host where cybersecurity analysis will be performed. DNS Firewall applies the same security policy to all clients, whereas Client Query Filtering is able to apply specific policies to groups of clients and apply either allow lists or deny lists.