What is a DNS malicious attack? Core concepts and typical type resolution

the underlying architecture of Internet communication, the DNS system is like the address book of the online world, responsible for converting domain names into Internet Protocol Addresses that can be recognized by devices. However, this critical system is often the target of network attacks. DNS malicious attacks not only interfere with normal network access, but also may lead to serious consequences such as user information leakage and property loss. This article will deeply analyze the core concepts of DNS malicious attacks, disassemble their typical types, and share practical identification and protection methods to help readers fully understand such cyber threats.

What is the core concept of DNS malicious attack?

to understand DNS malicious attacks, it is first necessary to clarify the basic logic of its nature and operation, which is the premise of identifying and preventing such attacks.

1, the definition of DNS malicious attacks

DNS malicious attack refers to the attacker through a variety of technical means, DNS system query, analysis, response and other links to interfere or tamper, thereby destroying the normal process of domain name resolution, illegal theft of information, inducing users to visit malicious sites, initiate network blocking and other purposes of attack behavior. This kind of attack takes advantage of the openness and trust mechanism of the DNS system, often has the characteristics of strong concealment and wide influence.

2, the operation basis of DNS malicious attacks

The distributed architecture and caching mechanism of the

DNS system are the key to its efficient operation, and it has also become a breakthrough for DNS malicious attacks. Attackers can use the valid period rule of the cache to plant false resolution records, or use the trust relationship of the open recursive server to amplify the attack traffic, and even directly tamper with the analysis results by forging response packets, so that users' network requests deviate from the normal track.

What are the typical types of DNS malicious attacks?

DNS there are various types of malicious attacks, different types of attack methods and degrees of harm vary, understanding these typical types can help readers accurately identify threats.

1, DNS hijacking attack

DNS hijacking is one of the most common types of DNS malicious attacks. The attacker points the legitimate domain name that the user originally wanted to visit to the malicious Internet Protocol Address by tampering with the resolution records of the DNS server, or implanting a false response in the transmission path between the user device and the DNS server. When the user visits the familiar domain name, it will be redirected to the counterfeit phishing website, which will lead to the theft of sensitive data such as account passwords and payment information.

2, DNS amplification attack

DNS amplification attack is a variant of Distributed Denial-of-service in which the attacker forges the victim's Internet Protocol Address and then sends a large number of query instructions containing large request packets to the open recursive DNS server. The DNS server will return much larger response data to the forged Internet Protocol Address, resulting in a traffic amplification effect that eventually causes the victim's Internet bandwidth to be exhausted and the service cannot be provided normally.

3, DNS cache poisoning attack

DNS cache poisoning attack refers to the attacker injecting false domain name resolution records into the cache of the DNS server. When other users query the domain name, the server will directly return the tampered false results. The harm of this kind of DNS malicious attack is persistent. As long as the cache record has not expired, all users who access the domain name will be affected, and the attack scope will continue to expand with the propagation of the cache.

How to identify the signs of DNS malicious attacks?

timely identify the signs of DNS malicious attacks, can effectively reduce the losses caused by the attack, which requires attention to abnormal performance in network access.

1, abnormal domain name jump phenomenon

when visiting a legitimate domain name for daily use, if you jump to an unfamiliar website, the content of the page does not match the original website, or are guided to a page containing advertisements and phishing links, it is likely to encounter a DNS malicious attack. This abnormal jump is a direct manifestation of tampering with the analysis results, and the operation needs to be suspended immediately and the problem needs to be checked.

2, network access speed drop or interruption

if there is no large traffic download or upload operation, the network suddenly has a sudden drop in speed, frequent cards or even complete interruption, be alert to the possibility of DNS amplification attacks. This kind of DNS malicious attack will generate a large amount of invalid traffic, occupying all internet bandwidth, resulting in normal network requests cannot be responded to.

How to effectively prevent DNS malicious attacks?

take multi-dimensional protection measures for the characteristics of DNS malicious attacks, which can reduce the risk of being attacked from the root cause and ensure the security and stability of network access.

1 Choose a secure and reliable DNS server

avoid using public DNS servers of unknown origin, and prefer the DNS service provided by the operator's official and certified security, or use the well-known third-party public DNS service. Such servers usually have comprehensive protection mechanisms, which can effectively block most DNS malicious attacks. At the same time, the security verification rules of the resolution records are regularly updated.

2, open DNS cache verification and encryption function

enable DNSSEC security extension function on the device and server side, which can effectively prevent DNS cache poisoning and hijacking attacks by verifying the authenticity and integrity of the parsing records through digital signatures. At the same time, encrypted DNS transmission protocols such as DoH or DoT are used to avoid parsing requests and responses being tampered with or monitored by attackers during transmission.

To sum up, DNS malicious attacks are common threats to the core system at the bottom of the network, and their types are diverse and harmful. By understanding its core concepts, being familiar with typical attack types, mastering the methods of identifying abnormal signs, and taking protective measures such as choosing a secure DNS server and opening encryption verification, the risk of DNS malicious attacks can be effectively reduced. In an increasingly complex network environment, paying attention to the security protection of DNS systems is an important part of ensuring personal and corporate cyber security.