Many website owners are often completely baffled when they first encounter the problem of "domain hijacking." Even though the server hasn't been touched and the website program hasn't been modified, users are redirected to unfamiliar websites, encounter pop-up ads, or even receive a "not secure" warning from the browser. This situation easily panics beginners, who may think the server has been completely hacked or the domain is about to be "ruined." In reality, domain hijacking is not uncommon, and in most cases, the cause can be identified and resolved. Once you understand its manifestations and causes, you won't be alarmed.

　　What does domain hijacking mean?

　　Domain hijacking, in essence, doesn't necessarily mean "domain ownership has been stolen." Rather, it means that when users access the domain, they are redirected to an address or content they didn't expect. This process can occur at multiple levels, including DNS, network links, the local environment, and even the user's own device. Because hijacking can occur at different stages, beginners often find the problem complex and don't know where to start.

　　Common Manifestations of Domain Hijacking:

　　One of the most common manifestations of domain hijacking in practice is being forcibly redirected to an advertising page or a gray-area website after accessing the domain. You enter your domain name in your browser, and the page flashes, the address bar instantly changing to a completely unrelated website. This is especially common on mobile networks and public Wi-Fi; accessing with mobile data will redirect, while accessing with broadband is normal, or vice versa. This phenomenon often misleads beginners into thinking their server has been compromised, but in reality, the server may be perfectly fine.

　　Another common manifestation is inconsistent access results across different regions and networks. For example, everything works fine at the office, but you are redirected at home; you access it without problems, but users report being constantly hijacked. This "intermittent" situation is a typical characteristic of domain hijacking because hijacking often occurs in DNS caching or network nodes, rather than the website program itself.

　　A third manifestation is that the domain access is occasionally normal, but strange ads, pop-ups, or scripts are inserted into the page. Sometimes this doesn't redirect the entire page, but rather "overlays" content onto the original website. When beginners see this phenomenon, their first reaction is often "the website has been compromised." However, in some cases, it's content injection by the ISP or malicious network nodes, not necessarily tampering with your website files.

　　Another alarming sign is when the browser directly warns "This website may be hijacked" or "Certificate insecure," especially in HTTPS scenarios. If you've configured the correct SSL certificate but still receive error messages, you need to be highly vigilant about potential DNS hijacking or man-in-the-middle attacks.

　　To truly resolve the issue, you must first understand at what level the hijacking is occurring.

　　One of the most common causes of domain hijacking is DNS-level hijacking. This typically manifests as the DNS records you see in your domain management backend being correct, but users are resolving to the wrong IP address. This is often because the local DNS, ISP DNS, or certain public DNS caches are poisoned, returning incorrect resolution results. DNS itself is a distributed system; if any node is tampered with or has an abnormal cache, it can lead to access problems in a local area.

　　Another common cause is domain account security issues. If your domain registrar account password is too simple, or if you've logged in on an insecure device, it's possible for someone else to gain control. Once they modify the domain's NS servers or DNS records, all access will be redirected to their designated address. This type of hijacking is usually widespread and long-lasting, making it the most dangerous, but also the easiest to detect through backend checks.

　　Another reason often overlooked by beginners is server or website program-level redirection. For example, a website might be infected with malicious code that redirects based on the access source, User-Agent, or time period. This type of hijacking sometimes only affects search engines or mobile devices; the website owner can access it normally, making it easy to misdiagnose as a DNS problem. While strictly speaking, this isn't exactly "domain hijacking," the user experience is almost indistinguishable.

　　Furthermore, there's the possibility of local environment hijacking. For example, malware might be installed on a computer or mobile phone, modifying the hosts file, or traffic might be hijacked through a proxy. In this case, only specific devices experience abnormal access; switching devices or networks restores normal access. Beginners, without comparative testing, can easily blame this on the domain or server.

　　Once the possible causes are identified, the troubleshooting approach becomes much clearer.

　　The first step is always to confirm whether the problem is widespread. You can access the domain name from different devices and networks (such as mobile data, home broadband, and company network) to see if the problem persists. You can also use online DNS lookup tools to check the domain name resolution results from different regions to confirm whether the correct IP address is being returned.

　　If the resolution results are inconsistent, prioritize suspecting DNS hijacking or poisoning. In this case, you can try switching to a reputable DNS service provider, such as a well-regarded cloud DNS, and reset the DNS records. Also, set the TTL to a reasonable value to avoid excessive caching and delays in repair. For poisoned caches, you can only wait for them to expire naturally or guide users to change their DNS servers.

　　If the investigation reveals that the domain name resolution has been modified in the background, or the NS has been changed, then it's almost certainly an account-level security issue. In this case, immediately change the domain registrar account password, enable two-factor authentication, check login logs, and restore the DNS to its correct state. If the damage is significant, contact the registrar's customer service for manual intervention.

　　If DNS is confirmed to be normal, but access remains abnormal, the focus of the investigation should be on the server and website programs. Check for abnormal redirect code, unfamiliar files, and tampered entry files, especially the homepage and public function files. Also, check the web server logs for abnormal requests or suspicious sources. Many hijacking attacks targeting novice websites exploit weak passwords, expired plugins, or vulnerabilities.

　　For HTTPS websites, it is strongly recommended to enable HSTS and ensure the certificate is configured correctly. HTTPS does not prevent all forms of hijacking, but it effectively prevents man-in-the-middle tampering and combats some network layer injection attacks.

　　In terms of daily prevention, the things beginners can do are actually quite simple. Choose reliable domain registrars and DNS service providers, and enable account security protection; avoid logging into the domain or server backend from untrusted computers; keep website programs and plugins updated; and regularly check for abnormal DNS records. These seemingly basic operations can prevent most domain hijacking problems.

　　Overall, domain hijacking is not an "unsolvable" disaster, but rather a problem that can be gradually solved through logical investigation. For beginners, the most important thing is not to panic, but to calmly assess the situation: is it a parsing problem, an account problem, a server problem, or a local environment problem? Once you're on the right track, solving the problem is often much simpler than you imagine.