How to prevent cross site scripting in OWASP?

How to prevent cross site scripting in OWASP?

Preventing all XSS flaws in an application is hard, as you can see. To help mitigate the impact of an XSS flaw on your site, OWASP also recommends you set the HTTPOnly flag on your session cookie and any custom cookies you have that are not accessed by any JavaScript you wrote.

Is there cheat sheet for DOM based XSS prevention?

This cheatsheet addresses DOM (Document Object Model) based XSS and is an extension (and assumes comprehension of) the XSS Prevention Cheatsheet. In order to understand DOM based XSS, one needs to see the fundamental difference between Reflected and Stored XSS when compared to DOM based XSS.

How does a DOM based XSS attack work?

DOM Based XSS (or as it is called in some texts, “type-0 XSS”) is an XSS attack wherein the attack payload is executed as a result of modifying the DOM “environment” in the victim’s browser used by the original client side script, so that the client side code runs in an “unexpected” manner.

How to categorize cross site scripting ( XSS )?

OWASP recommends the XSS categorization as described in the OWASP Article: Types of Cross-Site Scripting, which covers all these XSS terms, organizing them into a matrix of Stored vs. Reflected XSS and Server vs. Client XSS, where DOM Based XSS is a subset of Client XSS.

How to protect the security of an OWASP application?

If the application will be accessed from publicly shared computers such as libraries, the following may protect its security. Avoid caching the site’s pages on the system by setting the correct cache control directives. Exclude sensitive information from the site’s URLs since the history of the client browser will store these.

What happens when you refresh the second page on OWASP?

If a user clicks refresh on the second page (the page after login), the same request including the username and password in the POST will be sent again. If a valid user browses through the application and logs out, but does not close the window, an attacker could potentially click the back button of the browser to reach the second page.

How are session tokens assigned in OWASP application?

Alternatively, if the application has a login page which takes the user to an intermediate page for authentication, there they can be assigned a session token. Subsequently, even if the attackers reach the second page and refresh, the login information cannot be re-submitted.

How to prevent cross site scripting in Java?

ASP.NET 2.0 Framework has built-in ValidateRequest function that provides limited sanitization. The OWASP Java Encoder Project provides a high-performance encoding library for Java. The following rules are intended to prevent all XSS in your application.

When to redirect to a secure url in JavaScript?

One of those responsibilities is managing redirections. For example when you make an AJAX call to a secure service and without a valid authorization token. The service should return a 401 status code. When receiving a 401 status code the application should redirect the user to the login address.

When to accept JavaScript from an untrusted source?

Most importantly, never accept actual JavaScript code from an untrusted source and then run it. For example, a parameter named “callback” that contains a JavaScript code snippet. No amount of encoding/escaping can fix that. Rule #1 is for when you want to put untrusted data directly into the HTML body somewhere.