How to check if the website is contaminated? Practical testing skills are all shared

in the process of website operation, many webmasters will encounter abnormal page jumps, pop-up advertisements, inexplicable tampering and other problems. These seemingly scattered failures may point to the same hidden danger: the website is polluted. Pollution of the website will not only seriously affect the user experience, but also damage the reputation of the website, and even lead to search engine degradation. This article will share practical investigation and detection skills from multiple dimensions such as basic self-inspection, technical detection, and root cause positioning to help webmasters quickly lock the problem and solve it.

1. Self-examination of the basic symptoms of website contamination?

want to troubleshoot the problem of website pollution, we must first start from the intuitive symptoms, through the user's perspective and background observation, initially determine whether the website is abnormal.

1, front-end content abnormal troubleshooting

front-end is the part that users directly contact, and it is also the area where the problem is most likely to appear after the website is polluted. Webmasters can visit the website through different devices and different network environments to observe whether there are pages jumping to unfamiliar websites, pop-up advertising pop-ups that have nothing to do with the content of the website, the original text and pictures are tampered with, the loading speed drops sharply or the page cannot be opened directly. At the same time, it is also necessary to check whether the meta tags such as website titles and descriptions have been maliciously modified. These are typical front-end symptoms of website pollution.

2, background data and abnormal operation

In addition to the front-end performance, the abnormality in the background may also be a signal that the website is contaminated. Webmasters need to regularly check the login log in the background of the website to see if there is a login record of an unfamiliar Internet Protocol Address, or an abnormal operation log, such as unauthorized content modification, plug-in installation, etc. In addition, if the background cannot log in normally, the operation response is slow, and the function module is inexplicably missing, it is also necessary to be alert to the possibility of the website being contaminated.

Second, the website is contaminated technical tools detection?

can not accurately locate the problem based on symptom self-examination, with the help of professional technical tools, can more efficiently detect the specific situation of website pollution.

1, domain name resolution and DNS detection

DNS pollution is one of the common types of website pollution. Webmasters can query whether the Internet Protocol Address corresponding to the website domain name is correct through command line tools such as nslookup and dig. Compared with the Internet Protocol Address officially filed, if there is an inconsistency, there is a high probability that the DNS is polluted. In addition, online DNS detection tools can also be used to detect the resolution results of domain names in different regions and different DNS servers to determine whether there is a resolution abnormality.

2, website code and file detection

website is contaminated, malicious code is often embedded in the core file of the website. Webmasters can scan the HTML, CSS, JS files and server-side script files of the website with the help of code audit tools to detect whether there are unfamiliar code fragments, malicious jump scripts or hidden backdoors. At the same time, the file comparison tool can also be used to compare the current file with the backup file to quickly locate the tampered file and confirm the specific location of the website being contaminated.

Third, the root cause of website pollution positioning method?

after confirming that the website is contaminated, it is necessary to further locate the root cause of the problem in order to fundamentally solve the problem and avoid the reoccurrence of the website being contaminated.

1, server and host environment

server is the running carrier of the website. If the server security protection is not in place, it is easy to become a breakthrough for the website to be contaminated. The webmaster needs to check the firewall settings of the server to see if there are unauthorized ports open and abnormal process operation. At the same time, check the system log of the server to see if there are attack records of unfamiliar IP, illegal login attempts, etc. In addition, it is also necessary to confirm whether software or plug-ins from unknown sources are installed on the server, which may be the cause of the website being contaminated.

2, third-party plug-ins and interface detection

many websites will use third-party plugins and interfaces to enrich functions, but these external components may also become a hidden danger of website contamination. Webmasters need to check the third-party plugins and themes installed on the website one by one to see if there are any timely updated versions or unknown plugins. These plugins may have vulnerabilities and be exploited by attackers to cause the website to be contaminated. At the same time, it is also necessary to check the third-party interface called by the website to confirm whether the data returned by the interface is normal and whether there is any tampering.

4. Repair and verification after the website is contaminated?

find the source of the site is contaminated, it needs to be repaired in time, and through verification to ensure that the problem is completely solved, to prevent the site is contaminated recurrence.

1, targeted repair and cleaning

According to the root cause of the location, take corresponding repair measures: if DNS pollution, you need to contact the domain name service provider to reset the DNS resolution record in time, and replace the safe and reliable DNS server; if the code is tampered with, you need to use a clean backup file to replace the contaminated file and completely remove the malicious code; if the server is invaded, you need to reset the server system, strengthen the firewall rules, and update the system patch. For the website polluted by third-party plug-ins, you need to uninstall the suspicious plug-ins and update the genuine plug-ins to the latest version.

2, comprehensive verification after repair

after the repair is completed, multi-dimensional verification is required to ensure that the problem of website contamination has been completely solved. Webmasters can access the website through different devices and different networks again to check whether the front-end content is back to normal and whether the background operation is smooth; use technical tools to re-detect DNS analysis and code files to confirm that there is no abnormal residue; at the same time, continue to monitor the running status of the website and observe for 1-3 days to ensure that there are no symptoms of website contamination again.

To sum up, the investigation and solution of website contamination is a systematic process, from basic symptom self-inspection to technical tool detection, to root cause positioning and repair verification, each link is crucial. Webmasters need to be vigilant, regularly conduct safety inspections on the website, and master practical investigation skills, so as to respond quickly when the website is contaminated, solve the problem in time, and ensure the stable operation of the website and the good experience of users.