DNS Spoofing 101

Domain Name Server (DNS) spoofing is a method used by cybercriminals to redirect online traffic to a fraudulent website that resembles the originally intended destination of the users. It is also known as cache poisoning. Given the centrality of DNS in internet communications, being able to manipulate DNS entries allows cybercriminals to stage the perfect phishing scenario to collect confidential data.

Once the users access fraudulent websites, there is a big chance that they will unknowingly give away their passwords, credit card numbers, contact information, banking information, and data relating to their geographical location. This makes DNS spoofing one of the most dangerous techniques used by threat actors.

Methods for Executing DNS Spoofing Attack

Attackers have various options to carry out this attack. They may use premade tools or write their own attacking tools. They usually attack using public Wi-Fi networks since they are less secure. A home or business network usually has monitoring tools installed in them, making them vulnerable to spoofing attacks. The following are the methods for executing a DNS spoofing attack:

DNS Server Compromise

In this method, the DNS server is hijacked directly. It is then configured by the attacker to return a malicious IP address.

Man in the middle (MITM)

In this method, the attacker intercepts the communications between the DNS server and the users to route the users to malicious/fake IP addresses.

Why is DNS Spoofing so Dangerous?

DNS Spoofing is mostly carried out in public networks since it is poorly secured and often misconfigured. The counterfeit site displays elements of the original that are recognizable to the user and, at the same time, shows no signs that would make the victim suspect the site’s legitimacy.

Even if there were warning signs, users rarely notice them, and for this reason, spoofing often proves to be an effective method to take possession of the sensitive data of victims. DNS Spoofing attacks usually aim to steal victim data, so they pose a serious threat to data privacy.

Based on the goals of cybercriminals, a fake website will be developed. Suppose they want to get hold of banking information, for example. In that case, they will first go to a site of some popular banking service, download its code and stylesheets, and then upload it to the computer they control and use to hijack connections.

How Can ISPs Help Us Avoid DNS Spoofing?

Many internet service providers offer a DNS spoofing feature on routers to allow the router to act as a proxy DNS server while an interface setup for the ISP is down. The explicit understanding is that the router will return to its usual job of forwarding queries to DNS servers as soon as possible. However, DNS spoofing is also done for the purpose of deception. It is sometimes used in connection with spoofed websites to make the user believe that they have landed on the intended website.

This type of setup often uses a site where users enter usernames and passwords, account numbers, and other information that can be leveraged to make money. DNS spoofing differs from DNS hijacking, although it also takes the user to a different website than the one they attempted to reach.

The difference is that DNS hijacking doesn’t necessarily try to trick you into the URL you were directed to. For example, it has been used by some ISPs (Internet Service Providers) in the event of an NXDOMAIN error, i.e., when a URL is not found, probably because it is invalid so that instead of the error message, the user sees a replacement page, usually with advertisements, but nothing like the site the user was trying to reach.

How To Prevent DNS Spoofing?

Internet users can save themself from DNS spoofing attacks by using end-to-end encryption, domain name system security extension (DNSSEC), and DNS spoofing detection tools. Extra care should be taken when accessing the internet through public Wi-Fi. Employers working in an organization must be given awareness about cybersecurity best practices.

These practices may involve regularly scanning your PC for malware, flushing your DNS cache to solve poisoning, and never clicking on links that are unrecognizable. Many large-scale organizations prefer to use the Zero Trust framework to protect their network and ensure data privacy. Role-Based Access Control (RBAC) is used for user authentication and is the foundation of a Zero Trust security model.

Conclusion

In DNS spoofing, unsuspecting users, thinking they are accessing a legitimate website, do not realize that they have been redirected to the counterfeit website. Criminals typically leave no clues. They thoroughly test their fake sites before launching their attacks. However, occasionally some small errors can reveal the illegality of the fake site. For example, spoof sites usually don’t have any SSL certificates installed, so the connection is in cleartext.

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