DNS Hijacking vs. DNS Poisoning

Attribute	DNS Hijacking	DNS Poisoning
Definition	Unauthorized redirection of DNS queries to a malicious server	Modification of DNS records to redirect traffic to a malicious server
Goal	Intercept and manipulate DNS queries for malicious purposes	Redirect legitimate traffic to a malicious server
Method	Intercepting and redirecting DNS queries	Modifying DNS cache entries
Impact	Can lead to traffic interception, data theft, and phishing attacks	Can result in users being directed to fake websites or servers
Detection	Monitoring DNS traffic for unusual patterns	Checking DNS cache for unauthorized changes

Introduction

DNS hijacking and DNS poisoning are two common types of cyber attacks that target the Domain Name System (DNS). While both attacks aim to manipulate DNS records to redirect users to malicious websites, they differ in their methods and outcomes. In this article, we will explore the attributes of DNS hijacking and DNS poisoning to understand how they work and how they can be prevented.

DNS Hijacking

DNS hijacking is a type of attack where an attacker intercepts and modifies DNS queries to redirect users to malicious websites. This is typically done by compromising the DNS server or the user's device to change the DNS settings. Once the DNS settings are altered, any requests for a specific domain name will be redirected to a fake website controlled by the attacker. This can lead to sensitive information being stolen, such as login credentials or financial data.

One common method of DNS hijacking is through pharming, where attackers use malware to modify the hosts file on a user's device to redirect DNS queries. Another method is through DNS cache poisoning, where attackers inject false DNS records into the cache of a DNS server to redirect traffic. DNS hijacking can be difficult to detect, as users may not realize they are being redirected to a fake website until it is too late.

DNS Poisoning

DNS poisoning, also known as DNS cache poisoning, is a type of attack where an attacker corrupts the DNS cache of a DNS server to redirect users to malicious websites. This is typically done by sending false DNS responses to the DNS server, tricking it into caching the incorrect information. Once the DNS cache is poisoned, any requests for a specific domain name will be redirected to a fake website controlled by the attacker.

Unlike DNS hijacking, DNS poisoning does not require compromising the user's device. Instead, the attacker targets the DNS server directly to manipulate the DNS records. This makes DNS poisoning a more scalable attack, as it can affect multiple users who rely on the same DNS server. DNS poisoning can also be difficult to detect, as the fake DNS records are stored in the cache and can persist for a long time.

Comparison

While both DNS hijacking and DNS poisoning aim to redirect users to malicious websites, they differ in their methods and impact. DNS hijacking typically involves compromising the DNS settings on the user's device, while DNS poisoning targets the DNS server directly. DNS hijacking is often carried out through pharming or DNS cache poisoning, while DNS poisoning relies on sending false DNS responses to the server.

In terms of impact, DNS hijacking can lead to sensitive information being stolen from users who are redirected to fake websites. This can result in financial loss or identity theft. On the other hand, DNS poisoning can affect a larger number of users who rely on the same DNS server, making it a more scalable attack. Both attacks can be difficult to detect and mitigate, as they involve manipulating DNS records to redirect traffic.

Prevention

Preventing DNS hijacking and DNS poisoning requires implementing security measures to protect the DNS infrastructure. This includes using DNSSEC (Domain Name System Security Extensions) to cryptographically sign DNS records and prevent tampering. It is also important to regularly monitor DNS traffic for any signs of suspicious activity, such as unexpected redirects or changes in DNS settings.

Additionally, users can protect themselves from DNS hijacking by using secure DNS resolvers, such as Google Public DNS or Cloudflare DNS, which encrypt DNS queries to prevent interception. It is also recommended to keep software and security patches up to date to prevent malware infections that can lead to DNS hijacking. By taking these preventive measures, users and organizations can reduce the risk of falling victim to DNS hijacking and DNS poisoning attacks.