Which terminals are XSS attacks mainly targeting?

important role. However, what followed was the emergence of various network attack methods. One of the most common and widespread threats is cross-site scripting (XSS). This article will introduce what XSS attacks are and what end they mainly target, and give specific code examples.

XSS attack (Cross-Site Scripting) is a security vulnerability caused by improper processing of user input data by Web applications. Attackers inject malicious scripts into web pages so that when users browse the page, the malicious scripts will be executed. In this way, attackers can steal users' sensitive information, such as login credentials, personal privacy, etc. XSS attacks are widespread and easy to use, and are often used by hackers to carry out various network attacks, such as phishing, session hijacking, web page malware, etc.

XSS attacks are mainly oriented to the Web side, including front-end and back-end. Front-end XSS attacks are mainly based on improper processing of user input data. For example, when an application accepts user input such as form data, URL parameters, and cookies submitted by users, if the input is not effectively filtered or escaped, the attacker can inject malicious scripts. Reasons for this problem include over-trusting input data, not escaping special characters correctly, using unsafe JavaScript functions, etc. When users browse web pages injected with malicious scripts, these scripts will be executed, resulting in a successful attack.

Backend XSS attacks are mainly caused by the server not properly processing user input data. For example, if special characters in the query results are not properly filtered and escaped when data is queried from the database and displayed on the page, an attacker can attack other users of the website by injecting malicious scripts. Back-end XSS attacks are relatively more complex, and attackers usually try to use various escaping rules, tag closing mechanisms, etc. to bypass filtering measures.

In order to better understand the principles and harm of XSS attacks, several common code examples will be given below:

Example 1: Stored XSS attack

Assume a forum application , users can post comments on posts. The content of the comment will be stored in the database and displayed on the post page. If the server does not properly filter and escape comments submitted by users, attackers can commit XSS attacks by submitting malicious comments. For example:

<script>
  alert("恶意脚本");
  // 这里可以执行任意的攻击代码，如窃取用户信息等
</script>

Example 2: Reflected XSS attack

Assume a search page, the user can enter search keywords, and the results will be displayed on the page. If the server does not filter and escape user-entered keywords in search results, attackers can implement XSS attacks by constructing special search links. For example:

http://example.com/search?q=<script>alert("恶意脚本")</script>

Through this link, when other users click the link to search, the malicious script will be executed.

XSS attacks are very harmful and can be used to steal users' sensitive information, tamper with web pages, hijack user sessions, etc. In order to prevent XSS attacks, developers need to fully understand the principles and defense mechanisms of XSS attacks when writing web applications, and take appropriate filtering and escaping measures to protect users' security. At the same time, users also need to remain vigilant and avoid clicking on suspicious links and visiting unknown web pages to reduce the risk of XSS attacks.

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