What Is DNS Spoofing?

Domain Name Server (DNS) spoofing is a cyber attack where threat actors manipulate DNS records to redirect users to fraudulent or malicious websites that may resemble users’ intended destinations.

When users land on the fake sites, they are tricked into logging in to what seems to be their genuine accounts. This lets attackers steal their access credentials or other sensitive information. The malicious websites can install malware on users’ computers in the background, giving threat actors prolonged access to the victims’ devices and data.

Other interesting terms

Read More about DNS Spoofing

The attack is just one of the many cyber threats that pose risks to organizations’ DNS infrastructure. Learn more about it here.

How Does DNS Spoofing Work?

Did you know that most threat actors use prebuilt tools available on the Dark Web to carry out the attack? Note, though, that some more advanced attackers can create their own tools.

Also, bad guys often target free public Wi-Fi access points to get to connected devices. Why? They are either misconfigured and poorly secured, making them easier targets. But home or business networks can be vulnerable to the attack, too. That’s why it is a must to always think about Wi-Fi security.

Here’s a likely scenario.

Attackers find a public Wi-Fi network in a well-populated spot, typically a mall or cafe.
They send an Address Resolution Protocol (ARP) message or arpspoof command to trick target users’ devices into pointing to machines under their control when the victims access a popular domain. This essentially poisons the user devices’ resolution caches.
The attackers then send another arpspoof command to trick the domain’s web server into thinking the user devices’ IP addresses are the attacker’s machine IP address.
The threat actors create a HOST file entry pointing their machine’s IP address to the target website. This HOST entry is used when users request the domain name.
The attackers set up a phishing website that looks like the real site hosted on a local malicious computer.
The threat actors collect data from the victims’ devices by tricking them into entering their login information into the spoofed page.

What Are the Possible Effects of DNS Spoofing ?

The attack can have disastrous consequences, including but not limited to the ones cited below.

Data Theft

As shown in the steps above, attackers who successfully redirect users to their specially crafted phishing websites can collect their private information. The threat actors can then use the stolen credentials to hijack accounts or sell them to other cybercriminals.

Malware Infection

In many cases, attackers redirect users to malware-laden websites to infect the victims’ computers with malware. This is doable through drive-by downloads that automatically drop malware on user systems with the mere act of visiting a malicious page or by enticing victims to click a malicious link that installs malware.

Financial Loss

Imagine if the threat actors manage to redirect you to a fake bank login page and steal your credentials. If that happens, what’s to stop them from stealing all your money?

Increased Malicious Site Authority

If attackers continuously redirect traffic from legitimate websites to their fraudulent sites, they can increase their sites’ authority and search ranking. This helps them generate more website traffic to their fraudulent domains, making them even more effective lures for future attacks.

Halted Security Updates

If threat actors spoof an Internet security provider’s website, every time a user visits the site to update his security application, he will be sent to the wrong one and won’t get updated. Also, if the attackers substitute a piece of malware for the update, the victim’s computer gets infected instead.

Unwanted Censorship

Did you know that the Chinese government configures the entire nation’s DNS settings to ensure all users can only access approved websites? Some organizations also employ the tactic to prevent employees from visiting certain sites (e.g., adult websites) while at work. But attackers can use the same means to censor victims’ browsing, redirecting them to sites under malicious control instead of the legitimate ones the users often access.

What Are the Usual DNS Spoofing Tactics?

Threat actors often employ various techniques to launch attacks. We named some of the most popular tactics below.

1. Man-in-the-Middle Attack

In a man-in-the-middle (MitM) attack, attackers intercept the communications between users and a DNS server to redirect victims to a malicious IP address. By “standing” between users and the DNS server, threat actors can manipulate DNS responses and lead users to unintended destinations.

2. Domain Name System Server Hijacking

In DNS hijacking, threat actors hijack a DNS server they’ve configured to return a malicious IP address. By compromising the server, they can control the DNS resolution process and manipulate responses to redirect users to malicious sites.

3. Time-to-Live Exploitation

Here, attackers exploit the DNS server cache’s time-to-live (TTL) values. Specifically, they manipulate the TTL values to ensure incorrect DNS entries persist longer. By doing so, they increase the number of potential victims and prolong the attack’s duration. Even users who may not have been part of the target list can be redirected to malicious sites so long as the corrupt DNS responses remain in the cache.

4. Spamming

In this method, threat actors embed malicious code into spam emails that often try to scare users into clicking the link. When the victims do, they launch the attack.

How Can You Prevent DNS Spoofing ?

There are tons of ways to prevent the attack. Here are some of them.

Use DNS Security (DNSSEC) extensions: DNSSEC refers to a suite of specifications to secure certain kinds of information provided by DNS. It authenticates the origin and integrity of DNS data.

Use trustworthy DNS servers: The more trustworthy your DNS server, the more secure they are against the attack. These servers are highly secured and regularly updated and thus are less likely to be compromised.

Encrypt communications: Secure your communications with DNS servers using protocols like DNSCrypt. That way, you can ensure the responses you get solely come from trusted sources and have not been tampered with.

Regularly update systems: Keeping your DNS software up-to-date ensures they have the latest security patches.

Employ network security: Solutions like web application firewalls (WAFs), intrusion detection systems (IDSs), and intrusion prevention systems (IPSs) can help identify and block potential attacks.

Use Internet Protocol Security (IPSec): IPSec uses cryptographic security services to protect communications over IP networks. The measure enhances and secures data flow between a host and network or between networks.

Use DNS spoofing detection tools: These solutions scan all DNS data sent to your network to ensure its accuracy before allowing it to enter.

Never click links you do not recognize: Type a domain into your browser rather than click a suspicious-looking link in an email or web page.

Regularly scan for malware: The attack can deliver all kinds of malware to your computer. As such, regularly scanning can get rid of malware you accidentally downloaded.

Flush your DNS cache: Flushing your DNS cache gets rid of false information. This gives your device a fresh start, ensuring any DNS information it processes will correlate with the correct sites.

Use a virtual private network (VPN): A VPN ensures that all data going to and from your computer is encrypted.

Use a DNS firewall: A DNS firewall prevents users from visiting malicious websites that may drop malware onto their computers. Network administrators can also configure the firewall to block sites employees aren’t allowed to visit.

Why Is DNS Spoofing Also Known as “DNS Poisoning”?

In many cases, DNS spoofing is also called “DNS poisoning.” Why? The attack tricks users into divulging sensitive information or installing malware by poisoning the victims’ DNS caches to redirect them to sites under the attackers’ control.

As the definition stated, DNS spoofing requires changing or “poisoning” entries on DNS resolvers or servers to point them to different IP addresses.

How Does DNS Spoofing Differ from DNS Hijacking?

DNS hijacking is broader than DNS spoofing. In fact, DNS hijacking refers to any attack that tricks users into thinking they are communicating with legitimate domains when in reality they are accessing domains or IP addresses under attackers’ control. It is also called “DNS redirection.”

Given that DNS spoofing tricks users into visiting fake sites via DNS record manipulation, it falls under the bigger umbrella of DNS hijacking.

Here’s a summary of their differences.

DNS Hijacking	DNS Spoofing
Encompasses all attacks that involve redirecting users to malicious websites	DNS attack where attackers manipulate records to point users to malicious sites
Can be used to trigger a DNS spoofing attack	Can result from a DNS hijacking attack

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It’s easy for any user to fall for a DNS spoofing attack. What victims may not know, however, is that the attack is a huge threat to their data privacy. They can potentially lose their passwords and other private contact details to attackers. With enough information, attackers can open other accounts under the victim’s name or authenticate their logins to legitimate accounts to steal more information or money.

Note, though, that DNS spoofing may not always be nefarious, it can also be employed for legitimate censorship.

Key Takeaways

DNS spoofing is a cyber attack where threat actors manipulate DNS records to redirect users to fraudulent or malicious websites that may resemble users’ intended destinations.
To launch the attack, threat actors follow six steps—find a poorly secured Wi-Fi network, use arpspoof to poison a user’s DNS resolution cache, use arpspoof to spoof victims’ IP addresses, make a HOST file entry to point their IP address to the target site, creates a phishing site, and steals users’ login credentials.
Date theft, malware infection, financial loss, increased malicious site authority, halted security updates, and unwanted censorship are some of the attack’s possible consequences.
MitM attacks, DNS server hijacking, and TTL exploitation are some of the tactics used for the attack.
Using DNSSEC, trustworthy DNS servers, IPSec, DNS spoofing detection tools, VPNs, and DNS firewalls is just one of the many ways to prevent the attack. Other best practices include encrypting network communications, regularly updating systems, employing network security, never clicking suspicious links, regularly scanning for malware, and flushing DNS caches.