DNSSEC – Definition

DNSSEC explained.

The Domain Name System Security Extensions, or for short DNSSEC, is an excellent method to improve the security of your domains. It is a superior DNS trait. When you start applying it to each DNS record is going to be attached a digital signature (DS) record. That provides a guarantee that the domain name source is authentic.

The main reason for its creation is to keep the users on the Internet safe and protected from any forged DNS data. For example, the address could be misleading or malicious and lead users to an unwanted website rather than the original one they requested.

When you start using DNSSEC, the DNS lookups are going to prove that the source of the website’s DNS is valid with digital signatures. Therefore, some types of attacks could be successfully stopped through its help. That is possible because the browsers will not open the site if the digital signature does not match.

How does it work?

DNSSEC is fixing the safety problems that concern DNS, which needs a cover of security on top. 

The answer is the authentication method that applies digital signatures with public-key cryptography – DNSSEC. With its help, the owner of a DNS service is able to cryptographically sign the DNS data for their domain name. It is essential to know that we are not speaking about the DNS queries themselves. 

To achieve that, every DNS zone requires a combination of a public and a private key. 

The domain owner uses the private key to sign the information in the zone. 

The public key is visible publicly, and it is placed in the zone.

Each DNS recursive server that wants to review data in the zone will receive this public key and confirm the authenticity of the DNS records. This occurs if it successfully authenticates the information. If not, the DNS recursive server is going to give an error message to the user. 

The information in the authoritative name server additionally requires to verify its authenticity. Its public key is confirmed, not by its own private key, but from the authority on top. The root zone does not have someone on top to sing its key.

What does it protect against?

The foremost aim of DNSSEC is to provide restrictions to third parties to attempt to falsify any DNS records. Limiting the following situations from happening, it is capable of protecting the integrity of the domain name.

DNS Cache Poisoning

It is considered a sort of man-in-the-middle attack. The attackers’ goal is to flood a DNS resolver with bogus DNS information. There are cases in which the attacks can progress a lot and establish a fake end result in the cache memory of the resolver. For that reason, the DNS resolver supplies a malicious and fraudulent address to all users that ask for that particular website. Unfortunately, it lasts till the TTL (Time-to-Live) expires.

Fabricated zones

DNSSEC can protect against DNS attacks that unfairly use the DNS system and supply simulation results for zones. They may not exist, really, and criminals profit from holes among zones. So DNSSEC produces mechanisms for these holes to not being used and secure the complete zone.