What is a DNS sinkhole and how can it be used to prevent malware?

by | Oct 16, 2019 | CCNA, CCNP, CompTIA, Data Breaches and Prevention, Data Security, Email Security, End Point Protection, Exclusive Articles, File Less Malware, Malware Prevention, Network Security, Phishing, Ransomware Prevention, Rootkits and Prevention

DNS Sinkhole

What is a DNS sinkhole?

Let’s say an employee of a company has received one phishing email. He could not recognize the phishing attempt and clicked on the phishing link or opened an attachment to the email. As a result, the employee’s system tries to connect to the malicious server. In order to do so, the computer will first resolve the IP address of the malicious domain by sending a DNS query to a DNS server. A DNS sinkhole is a DNS server that spoofs an authoritative DNS server and when a computer tries to resolve the IP address of a malicious domain, the DNS sinkhole returns a false IP address instead of the actual IP address of the malicious server.


In this article, we will discuss:

  • What is DNS Sinkhole?

  • How does DNS Sinkhole work?

  • What are the use cases of DNS Sinkhole?

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Amrita Mitra

Author

Ms. Amrita Mitra is an author, who has authored the books “Cryptography And Public Key Infrastructure“, “Web Application Vulnerabilities And Prevention“, “A Guide To Cyber Security” and “Phishing: Detection, Analysis And Prevention“. She is also the founder of Asigosec Technologies, the company that owns The Security Buddy.

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