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What are DNS cache poisoning and DNS spoofing?

Domain Name System & # 40; DNS & # 41; Poisoning and spoofing is a type of cyberattack that exploits a DNS server vulnerability to redirect traffic from a legitimate server to a fake server. After visiting a malicious site, you may not be wondering how to solve the problem. Only you can do it. You need to know exactly how it works to protect yourself.

DNS spoofing, and therefore DNS cache poisoning, is one of the more deceptive cyber threats. If you don’t understand how the Internet connects to your website, you might think that the website itself has been hacked. In some cases, it may just be your device. To make matters worse, cyber security suites can only stop some of the threats associated with DNS spoofing.

What is DNS? What is a DNS server?

DNS stands for “Domain Name System.” However, before discussing the DNS server, it is important to clarify the terms related to this topic.

Internet Protocol (IP) address is a unique computer and server number string identifier name. These IDs are used by computers to search and “communicate” with each other. A domain is a text name that people use to remember, identify, and connect to a particular website server. For example, a domain like “” is used to easily find the actual target server ID. H. IP address – to understand.

Domain Name System & # 40; DNS & # 41; Used to translate a domain to its corresponding IP address. The Domain Name System Server (DNS Server) is a collection of four types of servers that make up the DNS lookup process. These include resolution of name servers, root name servers, top-level domain (TLD) name servers, and authoritative name servers. For the sake of simplicity, we will only discuss the details of the resolver server here.

The resolution name server (or recursive resolver) is a translation component of the DNS lookup process that resides in the operating system. It is designed to require a large number of web servers for the destination IP address of a domain name.

How DNS lookup works

Web Browsers and Operating Systems & # 40; OS & # 41; Try to get the IP address associated with your domain name. During your last visit, the IP address may be obtained from your computer’s internal memory or memory cache. If the component does not know where the destination IP address is, the process will continue. The operating system queries the name server to resolve the IP address. This query initiates a server chain search to find an IP that matches your domain. Eventually, the resolver finds the IP address and sends it to the operating system, which returns it to the web browser. The DNS lookup process is the basic framework used throughout the Internet. Unfortunately, criminals can exploit DNS vulnerabilities. In other words, you need to be aware of the possibility of redirects. To help you, let’s explain what DNS spoofing is and how it works.

DNS Cache Poisoning and Spoofing Mechanism

There are two main threats to DNS.

DNS spoofing is a threat that results from imitating legitimate server destinations to redirect domain traffic. Unquestioned victims end up on malicious websites that are targeted by various methods of DNS spoofing attacks. DNS cache poisoning is a user-side method of DNS spoofing where the system records incorrect IP addresses in the local storage cache. This will cause DNS to call back the problematic website specifically for you, even if the problem is fixed or does not exist on the server side. DNS spoofing or cache poisoning attack method

The more common of the various DNS spoofing attack methods are:

  1. Man-in-the-middle attack: When an attacker moves between a web browser and a DNS server and infects both. The tool is used to do cache poisoning on the local device and server poisoning on the DNS server at the same time. As a result, you are redirected to a malicious website hosted on the attacker’s own local server.

  2. DNS server hijacking: Criminals reconfigure the server directly to direct all requesting users to malicious websites. An IP request for a fake domain leads to a fake website when a bad DNS record is inserted into the DNS server.

  3. DNS cache poisoning via spam: DNS cache poisoning code is common in URLs sent via spam email. These emails try to trick the user into clicking on the URL provided. This infects your computer. Banner ads and images on both email and untrusted websites can also lead users to this code. After being addicted, your computer leads you to a fake website that makes you look real. This is where the actual threat to the device arises.

How to Prevent DNS Cache Poisoning and Spoofing

When looking to prevent DNS spoofing, user end protections are limited. Website owners and server providers are a bit more empowered to protect themselves and their users. To appropriately keep everyone safe, both parties must try to avoid spoofs.

Here`s how to prevent for website owners and DNS service providers:

  • DNS spoofing detection tools

  • Domain name system security extensions

  • Endtoend encryption

  • Here`s how to prevent for endpoint users:

  • Never click on a link you don`t recognize

  • Regularly scan your computer for malware

  • Flush your DNS cache to solve poisoning

  • Use Virtual Private Network (VPN)

Prevention Tips for Website Owners and DNS Server Providers

As a website owner or DNS server provider, the responsibility to defend users is firmly in your hands. You can implement various protective tools and protocols to keep threats out. Among these resources, you would be wise to use some of the following:

DNS spoofing detection tools: As an equivalent of endpoint user security products, these detection tools proactively scan all data received before sending it out. Domain name system security extensions (DNSSEC): Essentially a DNS “verified real” label, the DNSSEC system helps keep DNS lookup authentic and spooffree. Endtoend encryption: Encrypted data sent for DNS requests and replies keeps criminals out as they won`t be able to duplicate the unique security certificate for the legitimate website. Prevention Tips for Endpoint Users

Users are particularly vulnerable in these to avoid being a victim of a DNS poisoning attack, you should follow these simple tips:

Never click on a link you don’t recognize. This includes email, text messages, or links in social media. Tools that shorten URLs can further mask link targets, so avoid these as much as possible. For added security, always choose to manually enter the URL in the address bar. However, do this only after confirming that it is officially legal. Regularly scan your computer for malware. DNS cache poisoning may not be detected, but security software can be used to detect and remove secondary infections. Fake websites can contain all sorts of malicious programs, so you should always check for viruses, spyware and other hidden issues. The reverse is also possible, as malware can deliver spoofing. To do this, always use a local program, not the hosted version, as addiction can spoof web-based results. If necessary, clear the DNS cache and fix the poisoning. Unless you clean up the infected data, cache poisoning will stay in your system for a long time. This process can be as simple as opening the Windows “Run” program and typing “ ipconfig /flushdns” as your command. Mac, iOS, and Android also have flush options. These are usually found in a “network settings reset” option, toggling airplane mode, via device reboot, or in a specific native web browser URL. Look up your specific device`s method for guidance. Use a virtual private network (VPN)