In website operation, comment sections and message boards are important channels for interacting with users and collecting feedback.However, this area where users can freely fill in content often becomes an entry point for potential security risks, especially cross-site scripting (XSS) attacks.As website administrators, we must ensure that the content entered by users is safe to display on the front end and is not maliciously exploited.Auto CMS, a system focused on providing secure and efficient content management solutions, offers us powerful tools to deal with such challenges.escapejsIt can help us safely handle the text submitted by users that may contain malicious JavaScript code.
Understand the risks of cross-site scripting (XSS) attacks
<script>alert(document.cookie);</script>If the website does not perform appropriate security handling, this code may be executed in the browsers of other users, thus stealing the users' Session Cookie.Therefore, it is the foundation of website security to strictly filter and escape all user inputs.
Security mechanisms built into the Anqi CMS template
The template engine of AnQi CMS (similar to Django syntax based on Go language) considered security from the beginning of its design. By default, all through{{变量}}The text output will be escaped as HTML entities. This means that if the user enters<script>alert('XSS');</script>It is not parsed by the browser as executable JavaScript code, but displayed as is on the page.<script>alert('XSS');</script>This is a very important security mechanism, which effectively prevents most XSS attacks based on HTML.
However, in certain special scenarios, for example, when we need to display the rich text content submitted by users (which may contain legitimate HTML tags), we may use|safeFilter.|safeTell the template engine that this content is safe and does not require escaping. But please note that only when weFully trustedThis content source, or has been strictly cleaned and filtered on the backend, can be used|safeotherwise, it will open a gap for XSS attacks.
escapejsFilter: JavaScript Context Security Guardian
So,escapejsWhat time does the filter come into play?Its main function is to escape special characters in text at the JavaScript level, making it safe to be embedded as part of a JavaScript string in the page.\uXXXXThe form, thus preventing the malicious code entered by the user from breaking through the boundaries of JavaScript strings, and then executing arbitrary JavaScript code.
In the templates of AnQi CMS,escapejsThe usage is very intuitive:{{ obj|escapejs }}For example, if we want to pass the user submitted comment content as a parameter in a JavaScript function, or dynamically fill it into some JavaScript variable, we should useescapejs.
Assuming we have a JavaScript function that needs to display the user's comment content:
<script>
function displayComment(commentText) {
alert(commentText);
}
</script>
If the user enters你好，世界！'); alert('XSS'); //such content, we can directly use{{ user_comment }}output and pass todisplayCommentfunction, would lead to the subsequentalert('XSS');is executed. The correct approach is to useescapejs:
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