What is DNS spoofing and cache poisoning?


In April 2022, hackers targeted the customers of eight Malaysian banks tricking them into downloading malicious apps. The apps stole user credentials and forwarded the messages to malware operators. Bad actors love social engineeringand even distribute the spoofed websites via Facebook ads.

This is just one of the cybercrimes reported in 2022, and the list goes on. According to Cybercrime Magazine, people have lost more than $6 trillion to malicious and fraudulent activity in 2021 alone.

Statistics like these make it essential to know the different types of impersonation attacks and ways to prevent them.

However, this piece focuses on what is DNS spoofing and cache poisoning, actions that often lead to larger cybersecurity issues. The danger with these is that they are often not visible to the naked eye of an unsuspecting user. First, let’s define what a Domain Name System (DNS) is.

What is DNS?

A domain name system (DNS) is like a quick-access phone book. If you want to call a friend, just do so using the contact details stored on your phone; that way you don’t have to memorize everyone’s number.

Similarly, the Internet uses a directory called DNS. All computers (including your cell phones and tablets) are associated with an exclusive number called an IP address linked to a domain name.

So every time you want to visit a website, there is no need to type in the long IP address – you can just type in the domain name. For example, amazon.com. DNS is what turns the simple domain name into an IP address that devices can understand.

DNS typically contains other information, including but not limited to SPF and DKIM records.

What is a DNS lookup?

In general, DNS lookup refers to checking the DNS record when it comes back from the DNS server. It’s like how we check the directory to know the caller; it translates people’s email addresses and domain names into numbers (IP address).

What is DNS spoofing?

DNS spoofing is a common type of cyberattack in which the hacker uses modified DNS records to direct traffic to a fake website. This is usually done to obtain personal information or trick the target into making payments to the impersonator’s account.

Sometimes the fake dns instructs the target to log into a fake account (which they think is real), and eventually their credentials are stolen to cause harm. Most of them DNS spoofing In some cases, malicious websites install viruses in your device to get data for a long time.

Attack steps

How does DNS spoofing work? Here’s a quick breakdown:

  • Recognition: Hackers learn everything about the victim’s environment through publicly available DNS data. This exercise is not short term. Instead, it aims to plan a bigger scam in the long term. Thus, they secretly get the target’s information to launch the DNS spoofing load.
  • To access: Attackers abuse free access to find unauthorized entries in the DNS zone. Authoritative nameservers create new DNS records because they accept dynamic updates.
  • Offensive: The goal is to cause Denial of Service (DoS) or Man-in-the-Middle attacks, which aim to flood the server to the point where the system comes to a complete halt. These guidelines will let you know how to detect dns spoofing.

DNS spoofing versus DNS cache poisoning

Terms DNS spoofing and DNS cache poisoning are used interchangeably; however, there is a difference between the two. In fgeneral, DNS cache poisoning is one of the ways to initiate a DNS spoofing attack.

There are several ways to carry out this cyberattack like compromising the DNS server, mounting DNS cache poisoning, man-in-the-middle techniques, guessing the sequence number, etc.

While in the DNS cache poisoning method, the attacker falsifies a DNS and injects it into the records to obtain, abuse, hijack or modify incoming and outgoing information.

Why is DNS Spoofing dangerous?

DNS spoofing carries great risks, because your DNS contains crucial information about your domain. This can open a massive vulnerability and lead to anything from man-in-the-middle attacks to malware infestation. Let’s discuss some of the potential problems with DNS cache poisoning.

Malware infection

This is one of the common risks associated with a DNS spoofing attack in which the target is directed to a malicious website with virus-infested downloadable links.

According to EfficientIP Global DNS Threat Report 2020nearly 79% of companies surveyed were victims of DNS attacks in 2020. On average, each company lost $924,000 to pirates.

Data loss

Often, attackers who employ DNS spoofing aim to steal data from banks and telecommunications companies. In doing so, they compromise the personal and business data of the customers of these organizations.

Hinder updates

DNS spoofing also hinders security updates if the spoofed website includes internet service providers. This means that your system is not protected against evolving viruses and phishing attacks.

Government censorship

Sometimes the government of a country censors certain websites. These bans are usually for pornography or political content. Many authoritarian countries have huge lists of censored content, including anything related to women’s rights, politics, religion, and social media sites.

How to prevent DNS spoofing?

Now that we’ve discussed what is a DNS spoofing attack?let’s find out how to prevent it.

As many as 4.29 billion people use the internet for various purposes, increasing exposure to usurpers. In this section we will talk about how to prevent DNS spoofing:

Use detection tools

Human capacity is limited in viewing DNS queries, so DNS spoofing detection is something that should be left to the proper tools to analyze all incoming and outgoing data packets.

Use DNS Security Extensions (DNSSEC)

Another possible way to prevent DNS cache poisoning is to deploy the DNSSEC protocol, which operates on a unique cryptographic signature registered with other DNS records.

Configure end-to-end encryption

Implementing an end-to-end encryption protocol will prevent the impersonator from making a copy of the unique security certificate belonging to the originating website. Discover the ways to recognize email spoofing to better understand this.

Scan your devices for malware

Installed malware detection software helps you get rid of viruses, spyware and other hidden programs that take over cache poisoning. Moreover, it is necessary to use a downloaded program because the poisoning could also falsify the online search results.

Do not visit suspicious sites, including via URLs

Don’t click on links you don’t recognize or are suspicious of. Links and hyperlinked icons on social media, email and SMS are the gateways to DNS cache poisoning; therefore, you have to manually enter the URL in the search bar.

Use a VPN

A virtual private network (VPN) works like an encrypted tunnel to protect your privacy, especially on an unknown network. Browsing using a VPN largely prevents you from all kinds of identity theft. If you use public WiFi frequently, this is a must for you.

Flush your DNS

Rinse the DNS cache prevents a poison attack by getting rid of the infected data. Open the Windows “Run” program and type “ipconfig /flushdns; and you can stop yourself from DNS spoofing.

Getting rid of DNS cache poisoning is difficult

Determining whether DNS responses are fake or genuine is a tricky business. Proper DNS monitoring tools are essential to detect any anomalies. Nevertheless, you should also apply the preventive measures we have shared to stay safe on the Internet.

The post office What is DNS spoofing and cache poisoning? appeared first on EasyDMARC.

*** This is a syndicated blog from the Security Bloggers Network of EasyDMARC written by EasyDmarc. Read the original post at: https://easydmarc.com/blog/what-is-dns-spoofing-and-cache-poisoning/

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