What is DNSSEC and How Does it Work?

DNSSEC (Domain Name System Security Extensions) adds a crucial layer of security to the Domain Name System (DNS), which translates domain names into IP addresses.   However, DNS system is vulnerable to cyberattacks like DNS spoofing and DNS cache poisoning. You heard that right. These attacks can redirect users to malicious websites, leading to data theft or financial losses. 

According to IDC’s Global DNS Threat Report, in 2022, 88% of companies reported that they faced a DNS attack that cost them $942,000 on average. DNSSEC helps prevent these attacks by ensuring that you only connect to legitimate websites. 

So, if you’re concerned about keeping your online presence secure, here’s everything you need to know about DNSSEC.

What is DNSSEC?

DNSSEC adds a security layer to DNS that verifies this information is correct and hasn’t been tampered with by attackers. DNSSEC is a DNS protocol extension designed to add security features that protect the DNS from various types of cyber attacks. 

The DNS acts as the internet’s directory which translates names like “example.com” into IP addresses that computers use to connect. However, the standard DNS was not built with security as the top-most priority which was a mistake as it made it vulnerable to different cyberattacks. 

One thing to make clear is that DNSSEC is not designed to encrypt data but only to ensure the accuracy and authenticity of DNS responses. Because of this, it has become a necessary tool for protecting users and organizations from phishing attacks, man-in-the-middle attacks, and other security threats.

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Why DNSSEC Matters in Cybersecurity

Organizations that adopt DNSSEC protect themselves as well as their users from certain cyberattacks. Cyber threats are becoming more sophisticated day by day. Studies reveal that out of the 88% of companies that were attacked, 31% of them experienced brand damage meaning consumers lost trust in their brand. This shows how devastating this can be if preventive measures are not used. 

Implementing DNSSEC is a proactive step in defending against evolving threats and maintaining a secure digital environment for organizations and their clients. 

How Does DNSSEC Work?

Here’s how DNSSEC works, step by step:

1. Adding Digital Signatures to DNS Records

When a domain is secured with DNSSEC, its DNS records (like A, MX, or TXT records) are digitally signed. These cryptographic signatures are created using public-key cryptography. The domain owner generates a pair of cryptographic keys when DNSSEC is used.

• The private key is used to sign DNS data, creating DNSKEY records. It generates a unique digital signature for each record.
• In DNSSEC, zone-signing keys (public keys) are published in the DNS system so that anyone can verify digital signatures on DNS records. This ensures cryptographic authentication and data integrity of DNS responses.

2. DNS Resolver Requests a Domain

When a user tries to visit a website their device sends a request to a DNS resolver to find the IP address associated with the domain name in the DNS namespace. The DNS resolution process begins when a user enters a domain name in their browser. The browser sends a recursive DNS query to a recursive resolver, typically managed by the ISP. 

If the resolver doesn’t have the IP address cached, it queries a series of servers: DNS root name servers, top-level domain (TLD) servers, and authoritative name servers. These servers collaborate to locate the correct IP address, which is then sent back to the recursive resolver. 

The resolver caches this information for future use and returns the IP address to the user’s browser, allowing the webpage to load. If the authoritative server can’t find the information, it returns an error message, which in DNSSEC-enabled zones would include authenticated denial of existence proof.

3. Verification of Digital Signatures

The DNS resolver checks if the domain has DNSSEC enabled. If it does, the resolver uses the public key from the key pair to verify the digital signatures on the DNS records. Now there are two cases in this scenario: 

• If the signatures match then the resolver knows that the DNS data is authentic and hasn’t been tampered with. 
• If the signatures don’t match at all then the resolver rejects the response. It protects the user from connecting to a potentially malicious site. 

If you don’t know your DNS record names, use a DNS record checker to find them out.

4. Chain of Trust

DNSSEC operates on a concept called the “chain of trust”. At the top of the chain is the root zone of the DNS which is digitally signed. 

After that, each level of the DNS hierarchy (e.g., root → .com → example.com) validates the level below it by creating a secure chain. All this makes sure that every DNS response comes from an authoritative DNS server. 

5. Protecting Against Attacks

Lastly, DNSSEC protects users from attacks like: 

• DNS Spoofing: Prevents attackers from redirecting users to fake websites. It does this by ensuring DNS responses are authentic.
• Cache Poisoning: Stops malicious data from being stored in DNS resolvers.

What Does DNSSEC Do?

DNSSEC makes the internet safer by protecting DNS protocol data from being tampered with. As you already know DNS converts domain names into IP addresses but it doesn’t verify where the information comes from. This creates a risk of attacks which DNSSEC has the ability to solve. 

It protects against tampering by checking that no one has altered the DNS data during transmission. If attackers try to change the information, DNSSEC detects it and blocks the response. This helps users connect to the correct websites without worry. 

DNSSEC also confirms that DNS data comes from the right source, using a trust anchor as a foundation. It prevents hackers from pretending to be authoritative name servers and redirecting users to fake websites. Additionally, this builds trust, especially for industries like banking or healthcare where security is of utmost priority. 

In addition, DNSSEC supports compliance with modern security standards. Many organizations and governments now require DNSSEC to meet cybersecurity regulations. It also encourages businesses to adopt more advanced security tools to protect online activities further. 

Setting Up DNSSEC

Enabling DNSSEC for your domain is an important step to protect it from cyberattacks. Here’s how you can set it up in a simple and step-by-step process:

1. Access Your Domain Registrar’s DNS Settings

First, log into the account where you registered your domain name. Now go to the DNS settings section. This is the part of your account where you manage DNS record types like A, CNAME, or MX records. Most registrars have a separate option labeled “DNSSEC” to make it easier to find. 

2. Enable DNSSEC

Look for an option to turn on DNSSEC. Some registrars may even have a button or a switch to enable it. Once you activate DNSSEC, the registrar will create specific DNSSEC records for your domain. These records are necessary for the next steps. 

3. Add the DS Record to Your Domain’s DNS Settings

A DS record (Delegation Signer record) is a type of DNS record that links your domain to the DNSSEC system. The DS record contains important information like keys and algorithms that verify your DNSSEC setup. 

Copy the DS records from the registrar and paste this record into your DNS settings under the “Add Record” option. In the end, make sure you’ve pasted the correct record and saved it. 

4. Verify the Setup

After you’ve added the DS record, check if DNSSEC is working properly. For this, you need to use a DNSSEC checker tool. Many registrars also provide built-in verification tools to confirm the setup. 

The tool you’ll use will test your DNSSEC configuration and show if there are any errors. If everything is correct then your domain is not protected by DNSSEC. 

Challenges and Limitations of DNSSEC

While DNSSEC enhances the security of the DNS, it is not without its challenges. It’s important to understand these issues which include:

1. Implementation Complexity

It can be quite a headache to set up DNSSEC, especially for people who are not familiar with DNS management at all. So if there are even small errors in the setup, it can cause DNS resolution failures.

2. Increased DNS Response Size

DNSSEC adds digital signatures to DNS records. It significantly increases the size of DNS responses and leads to performance issues, especially on slower networks or older systems. Website performance, particularly DNS resolution time, significantly influences customer retention on a site versus switching to a competitor. Google’s research reveals a stark correlation between page load time and user bounce rates. When page load time increases from 1 to 3 seconds, the bounce probability rises to 32%, and when it reaches 5 seconds, the probability soars to 90%. For optimal user experience, DNS lookup should ideally take less than 100 ms, preferably under 50 ms. This allows 1-2 seconds for website content to load in the browser.

A webpagetest.org analysis of cisco.com illustrates this concept. The initial DNS lookup for cisco.com takes 25 ms, followed by a subsequent lookup for the www.cisco.com redirect, consuming an additional 33 ms. These DNS resolution times contribute to the overall connection delay and page load time, directly impacting user experience and potential customer engagement.

3. Lack of Widespread Adoption

Despite its benefits, DNSSEC is not used all over the world. According to APNIC’s 2023 report, only about 40% of the domains worldwide have implemented it. This means that it cannot protect users who are accessing unsecured domains which rescues the overall effectiveness of DNSSEC.

4. No Data Encryption

While DNSSEC ensures data integrity and authenticity, it does not encrypt DNS queries or responses. This means that the content of DNS requests can still be viewed by attackers. It leaves some aspects of user privacy unprotected. To solve this problem companies often use DNSSEC alongside DNS over HTTPS (DoH) or DNS over TLS (DoT).

5. Compatibility with DNS Forwarding

DNS Forwarding, which directs DNS queries from one server to another, can sometimes conflict with DNSSEC. If the forwarding server does not validate DNSSEC signatures, it may pass along unauthenticated responses. This weakens the overall system security.

Benefits of Using DNSSEC

DNSSEC offers several benefits to enhance the security and reliability of the DNS. Here are the key benefits of using DNSSEC:

1. Protects Against Cyberattacks

DNSSEC makes sure the DNS data has not been altered or forged by attackers. By digitally signing DNS records this security measure prevents cyberattacks. This protection is most important for protecting sensitive data and maintaining trust online. 

2. Enhances Trust in Online Services 

With DNSSEC, users can be confident that the websites they visit are authentic. This is particularly important for industries like banking, healthcare, and e-commerce, where trust is essential. DNSSEC creates a chain of trust from the root DNS name servers down to individual domains and thereby increases overall trust in internet services. 

For financial institutions, DNSSEC is of great significance in protecting both customers and the institution from fraudulent activities, especially given the sensitive nature of online banking transactions. In e-commerce, DNSSEC ensures that customers are not redirected to malicious websites, thereby protecting their financial information and preventing phishing attacks. 

Healthcare organizations also benefit greatly from DNSSEC. This is because it adds a vital layer of protection for safeguarding personal health information in online health services and medical records.

3. Supports Regulatory Compliance

DNSSEC is important for organizations to meet regulatory compliance across cybersecurity frameworks like GDPR, HIPAA, and NIST. It is also important for DMARC compliance as it secures DNS resource records such as SPF and DKIM. 

By implementing DNSSEC, organizations can demonstrate their commitment to robust security practices and data protection. This may prove particularly beneficial during audits and assessments as part of regulatory compliance processes. 

Furthermore, DNSSEC helps prevent DNS spoofing and cache poisoning attacks, which are important concerns for data privacy and integrity. As cyber threats continue to evolve, the role of DNSSEC in maintaining a secure and compliant infrastructure is likely to become even more apparent and significant.

4. Prevents Business Disruption

Cyberattacks on DNS can lead to website downtime, loss of customer trust, and financial losses. DNSSEC’s validation process reduces the risk of such attacks and helps businesses maintain uninterrupted services.

Final Words

DNSSEC is one of the most important tools for improving the security of your domain and protecting it from cyber threats. Ensuring DNS data is authentic and safe from tampering helps build trust and keeps users secure.

If you’re managing a website or an online service you should consider implementing DNSSEC to protect your domain.

If you have already implemented DNSSEC for your domain, check it now using our DNSSEC check tool – sign up for free!

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Milena Baghdasaryan

Content Specialist at PowerDMARC

Milena is a skilled writer and content creator with 7+ years of experience in crafting engaging content on IT, cybersecurity, virtual events, and more. She has a proven track record of delivering high-quality work for international magazines and is a graduate of prestigious institutions such as New York University Abu Dhabi, UWC China, and the College of Europe.

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