Is the js of javascript not automatically compiled?
JavaScript (JS) is a programming language widely used in web development, especially playing an important role in front-end development. Unlike other programming languages, JavaScript is interpreted and executed at runtime. Although this brings flexibility and convenience, it also brings some security issues.
JavaScript is not automatically compiled, which means that when viewing a web page in a browser, the JS code is dynamically parsed and compiled. This leaves some room for hackers to attack web pages and users' devices by injecting malicious code. In order to deal with such threats, we need to pay attention to the following aspects:
1. Use strict content security policy
Content security policy (CSP) is an important means of defense, which can Limit the source of code resources in web pages. By setting CSP, we can tell the browser to only allow JavaScript code to be loaded from specified domain names, ports, protocols, etc. This can prevent the injection of malicious code and improve the security of the website.
2. Use a Web Application Firewall
A Web Application Firewall (WAF) is a network security device that can filter and monitor website traffic. WAF can capture and filter out malicious HTTP requests and responses, preventing attackers from exploiting JS code vulnerabilities.
3. Regularly update and upgrade JS libraries and frameworks
JS libraries and frameworks are commonly used development tools. They provide many tools and methods that allow us to develop easily. But at the same time, since JS libraries and frameworks themselves also have vulnerabilities and security issues, they must be updated and upgraded regularly to ensure that the version used is the latest, which can reduce the risk of the website being attacked.
4. Avoid using functions such as eval and new Function that dynamically execute code
Both the eval and new Function functions can dynamically execute JavaScript code in the form of strings. This method is vulnerable to attackers. Injection attack. Therefore, try to avoid using these functions in your code and do not pass unvalidated user input as parameters to these functions.
In short, JavaScript JS code is vulnerable to injection attacks. In order to protect the security of users' devices and websites, we need to adopt higher security methods and policies. In actual development, we need to formulate corresponding security measures based on specific business scenarios and needs to ensure the safety and reliability of JS code.
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