What does DNS hijacking mean? The principle and harm of DNS hijacking are explained in detail

in daily network visits, have you ever encountered a situation where you enter a familiar URL but jump to an unfamiliar website, or the search results are forcibly replaced with advertising pages? These abnormalities are likely to hide the figure of DNS hijacking. As a common means of network attacks, DNS hijacking will quietly tamper with the direction of network access, not only affecting the normal online experience, but also may bring property damage and information leakage risk. This article will deeply dismantle the relevant knowledge of DNS hijacking, from principle to harm to prevention, to build a comprehensive cognitive system for you.

What is the basic concept of DNS hijacking?

to understand DNS hijacking, it is first necessary to clarify the core role of DNS, which is like the address book of the online world, responsible for converting easy-to-remember domain names into Internet Protocol Addresses that computers can recognize, allowing users to access websites without memorizing complex strings of numbers. And DNS hijacking is a malicious intervention in this conversion process.

1 Definition of DNS Hijacking

DNS hijacking, also known as domain name hijacking, refers to the attacker tampering with the result of DNS resolution by various means, pointing the domain name that the user originally wanted to visit to the wrong Internet Protocol Address, so as to realize the illegal purpose of jumping to malicious websites, planting advertisements or stealing information. It essentially destroys the authenticity of the corresponding relationship between the domain name and the Internet Protocol Address.

2, common classification of DNS hijacking

According to the different links of attack, DNS hijacking can be divided into local DNS hijacking and remote DNS hijacking. Local DNS hijacking occurs mostly in user equipment or local area network, such as malicious software tampering with local DNS settings; remote DNS hijacking is the attacker directly attacks the operator or public DNS server, tampering with the server's resolution records, and has a wider impact.

What are the main implementation principles of DNS hijacking?

DNS hijacking can be successfully implemented, because attackers take advantage of loopholes or weak links in the DNS resolution process, different types of DNS hijacking, the implementation principle is also different.

1, the principle of local tampering DNS hijacking

this type of DNS hijacking is mainly aimed at user devices or LAN environments. Attackers directly tamper with the local DNS server address of the device by inducing users to download malicious software, or implanting malicious routers in the LAN, or modify the domain name resolution record in the local hosts file. When a user initiates a domain name request, the device will preferentially use the tampered resolution information to jump to the designated malicious site.

2, server attack DNS hijacking principle

attackers will take advantage of DNS server security bugs, such as system vulnerabilities that are not fixed in time, weak passwords, etc., to illegally invade public DNS servers or operators' DNS servers, and directly modify the domain name resolution database in the server. In this way, all users who use the server for resolution will get the tampered wrong Internet Protocol Address, and then suffer DNS hijacking.

3, cache poisoning DNS hijacking principle

DNS server will store the recent resolution results in the cache in order to improve the resolution efficiency. The attacker will forge false resolution response packets and inject the wrong domain name IP correspondence into the cache of the DNS server. When the user requests the domain name, the server will directly return the error record in the cache, which is the cache poisoning DNS hijacking, which has a wide range of attacks and strong concealment.

What are the common hazards of DNS hijacking?

DNS hijacking is not just a simple jump exception, it will bring negative effects to users and enterprises from multiple levels, and even cause serious security accidents.

1, damage the user experience

this is the most intuitive harm of DNS hijacking. Users enter the correct URL but jump to the page full of advertisements, or are frequently directed to irrelevant websites. The normal network access process is interrupted, which greatly reduces the efficiency and experience of Internet access. Some DNS hijacking will also force pop-up advertisements to be implanted, occupying internet bandwidth, resulting in slower page loading.

2, stealing sensitive user information

attackers will direct users to counterfeit banking, e-commerce or social networking websites through DNS hijacking, which are highly similar to regular websites in interface and difficult for users to distinguish. When users enter account passwords, bank card information or verification codes on these counterfeit websites, all data will be stolen by attackers, which will lead to property damage or personal information leakage.

3, threat to corporate brand reputation

for enterprises, DNS hijacking will lead users to visit the false official website of the enterprise, if there is fraud or bad information on the counterfeit website, it will cause users to have a crisis of trust in the enterprise, seriously damage the brand perception and market reputation of the enterprise. At the same time, the customer resources of the enterprise may also be maliciously diverted, resulting in direct economic losses.

How to effectively prevent DNS hijacking?

face multiple risks of DNS hijacking, users and enterprises need to take targeted preventive measures to reduce the possibility of being attacked from the source and ensure the security of network access.

1 Choose a secure and reliable DNS server

avoid using DNS servers from unknown sources, and give priority to well-known public DNS servers in China or official DNS servers provided by operators. Such servers usually have perfect security protection mechanisms, which can effectively reduce the risk of being hijacked by DNS. At the same time, you can regularly check the DNS settings of the device to confirm that it has not been maliciously tampered with.

2, open the network encryption protection function

use a website that supports the HTTPS protocol, HTTPS can encrypt the data transmission process to prevent attackers from stealing or tampering with the parsing request. In addition, the DNS over HTTPS or DNS over TLS function can be turned on to allow DNS parsing requests to be transmitted through encrypted channels to avoid the parsing process being monitored or tampered with by attackers, and prevent DNS hijacking from the transmission link.

3, do a good job of equipment and network security maintenance

regularly update the operating system and antivirus software of the device, patch system vulnerabilities in time, and prevent malicious software from invading and tampering with local DNS settings. For LAN users, set complex router login passwords, turn off unnecessary remote management functions, and avoid attackers from implementing DNS hijacking through the router. At the same time, do not click unfamiliar links or download unknown software at will to block the attack entrance from the source.

To sum up, DNS hijacking is a kind of network attack method with strong concealment and wide range of harm. From the principle of tampering and analysis to the various risks caused, we need to be vigilant. By clarifying the concept and classification of DNS hijacking, mastering its implementation principle, identifying potential hazards, and cooperating with safe and reliable preventive measures, we can effectively reduce the probability of DNS hijacking, protect the cyber security of individuals and enterprises, and maintain normal network access order.