Projects/OWASP Java HTML Sanitizer Project

• Project Info
• Info
• Creating a HTML Policy
• Questions

PROJECT INFO What does this OWASP project offer you?

RELEASE(S) INFO What releases are available for this project?

what is this project? Name: OWASP Java HTML Sanitizer (home page) Purpose: The OWASP Java HTML Sanitizer Project is a fast and easy to configure HTML Sanitizer written in Java which lets you include HTML authored by third-parties in your web application while protecting against XSS. This code was written with security best practices in mind, has an extensive test suite, and has undergone adversarial security review https://code.google.com/p/owasp-java-html-sanitizer/wiki/AttackReviewGroundRules. The existing dependencies are on guava and JSR 305. The JSR 305 dependency is a compile-only dependency, only needed for annotations. The other jars are only needed by the unittests. Provides 4X the speed of AntiSamy sanitization in DOM mode and 2X the speed of AntiSamy in SAX mode. Very easy to use. It allows for simple programmatic POSITIVE policy configuration (see below). No XML config. Actively maintained by Mike Samuel from Google's AppSec team! Passing 95+% of AntiSamy's unit tests plus many more. This is code from the Caja project that was donated by Google. It is rather high performance and low memory utilization. Java 1.5+ License: New BSD License who is working on this project? Project Leader(s): Mike Samuel @ Jim Manico @ how can you learn more? Project Pamphlet: Not Yet Created Project Presentation: Mailing list: Mailing List Archives Project Roadmap: View Main links: https://code.google.com/p/owasp-java-html-sanitizer/ http://code.google.com/p/owasp-java-html-sanitizer/wiki/Maven Key Contacts Contact Mike Samuel @ to contribute to this project Contact Mike Samuel @ to review or sponsor this project

current release For more information goto https://www.owasp.org/index.php/OWASP_Java_HTML_Sanitizer_Project. last reviewed release Not Yet Reviewed other releases

A fast and easy to configure HTML Sanitizer written in Java which lets you include HTML authored by third-parties in your web application while protecting against XSS.

The existing dependencies are on guava and JSR 305. The other jars are only needed by the test suite. The JSR 305 dependency is a compile-only dependency, only needed for annotations.

This code was written with security best practices in mind, has an extensive test suite, and has undergone adversarial security review.

You can use prepackaged policies here: http://owasp-java-html-sanitizer.googlecode.com/svn/trunk/distrib/javadoc/org/owasp/html/Sanitizers.html.

PolicyFactory policy = Sanitizers.FORMATTING.and(Sanitizers.LINKS);
String safeHTML = policy.sanitize(untrustedHTML);

or the tests show how to configure your own policy here: http://code.google.com/p/owasp-java-html-sanitizer/source/browse/trunk/src/tests/org/owasp/html/HtmlPolicyBuilderTest.java

PolicyFactory policy = new HtmlPolicyBuilder()
   .allowElements("a")
   .allowUrlProtocols("https")
   .allowAttributes("href").onElements("a")
   .requireRelNofollowOnLinks()
   .build();
String safeHTML = policy.sanitize(untrustedHTML);

or you can write custom policies to do things like changing h1s to divs with a certain class:

PolicyFactory policy = new HtmlPolicyBuilder()
   .allowElements("p")
   .allowElements(
       new ElementPolicy() {
         public String apply(String elementName, List<String> attrs) {
           attrs.add("class");
           attrs.add("header-" + elementName);
           return "div";
         }
       }, "h1", "h2", "h3", "h4", "h5", "h6"))
   .build();
String safeHTML = policy.sanitize(untrustedHTML);

• How was this project tested?
  • This code was written with security best practices in mind, has an extensive test suite, and has undergone adversarial security review.
• How is this project deployed?
  • This project is best deployed through Maven https://code.google.com/p/owasp-java-html-sanitizer/wiki/Maven