DOMPurify

first

<script type="text/javascript" src="src/purify.js"></script>

<script type="text/javascript" src="dist/purify.min.js"></script>

const clean = DOMPurify.sanitize(dirty);

import DOMPurify from 'dompurify';

const clean = DOMPurify.sanitize('<b>hello there</b>');

const clean = DOMPurify.sanitize(dirty, { USE_PROFILES: { html: true } });

npm install dompurify
npm install jsdom

const createDOMPurify = require('dompurify');
const { JSDOM } = require('jsdom');

const window = new JSDOM('').window;
const DOMPurify = createDOMPurify(window);
const clean = DOMPurify.sanitize('<b>hello there</b>');

import { JSDOM } from 'jsdom';
import DOMPurify from 'dompurify';

const window = new JSDOM('').window;
const purify = DOMPurify(window);
const clean = purify.sanitize('<b>hello there</b>');

npm install isomorphic-dompurify

import DOMPurify from 'isomorphic-dompurify';

const clean = DOMPurify.sanitize('<s>hello</s>');

DOMPurify.sanitize('<img src=x onerror=alert(1)//>'); // becomes <img src="x">
DOMPurify.sanitize('<svg><g/onload=alert(2)//<p>'); // becomes <svg><g></g></svg>
DOMPurify.sanitize('<p>abc<iframe//src=jAva&Tab;script:alert(3)>def</p>'); // becomes <p>abc</p>
DOMPurify.sanitize('<math><mi//xlink:href="data:x,<script>alert(4)</script>">'); // becomes <math><mi></mi></math>
DOMPurify.sanitize('<TABLE><tr><td>HELLO</tr></TABL>'); // becomes <table><tbody><tr><td>HELLO</td></tr></tbody></table>
DOMPurify.sanitize('<UL><li><A HREF=//google.com>click</UL>'); // becomes <ul><li><a href="//google.com">click</a></li></ul>

window.trustedTypes!.createPolicy('default', {
  createHTML: (to_escape) =>
    DOMPurify.sanitize(to_escape, { RETURN_TRUSTED_TYPE: false }),
});

// strip {{ ... }}, ${ ... } and <% ... %> to make output safe for template systems
// be careful please, this mode is not recommended for production usage.
// allowing template parsing in user-controlled HTML is not advised at all.
// only use this mode if there is really no alternative.
const clean = DOMPurify.sanitize(dirty, {SAFE_FOR_TEMPLATES: true});

// change how e.g. comments containing risky HTML characters are treated.
// be very careful, this setting should only be set to `false` if you really only handle 
// HTML and nothing else, no SVG, MathML or the like. 
// Otherwise, changing from `true` to `false` will lead to XSS in this or some other way.
const clean = DOMPurify.sanitize(dirty, {SAFE_FOR_XML: false});

// allow only <b> elements, very strict
const clean = DOMPurify.sanitize(dirty, {ALLOWED_TAGS: ['b']});

// allow only <b> and <q> with style attributes
const clean = DOMPurify.sanitize(dirty, {ALLOWED_TAGS: ['b', 'q'], ALLOWED_ATTR: ['style']});

// allow all safe HTML elements but neither SVG nor MathML
// note that the USE_PROFILES setting will override the ALLOWED_TAGS setting
// so don't use them together
const clean = DOMPurify.sanitize(dirty, {USE_PROFILES: {html: true}});

// allow all safe SVG elements and SVG Filters, no HTML or MathML
const clean = DOMPurify.sanitize(dirty, {USE_PROFILES: {svg: true, svgFilters: true}});

// allow all safe MathML elements and SVG, but no SVG Filters
const clean = DOMPurify.sanitize(dirty, {USE_PROFILES: {mathMl: true, svg: true}});

// change the default namespace from HTML to something different
const clean = DOMPurify.sanitize(dirty, {NAMESPACE: 'http://www.w3.org/2000/svg'});

// leave all safe HTML as it is and add <style> elements to block-list
const clean = DOMPurify.sanitize(dirty, {FORBID_TAGS: ['style']});

// leave all safe HTML as it is and add style attributes to block-list
const clean = DOMPurify.sanitize(dirty, {FORBID_ATTR: ['style']});

// extend the existing array of allowed tags and add <my-tag> to allow-list
const clean = DOMPurify.sanitize(dirty, {ADD_TAGS: ['my-tag']});

// extend the existing array of allowed attributes and add my-attr to allow-list
const clean = DOMPurify.sanitize(dirty, {ADD_ATTR: ['my-attr']});

// prohibit ARIA attributes, leave other safe HTML as is (default is true)
const clean = DOMPurify.sanitize(dirty, {ALLOW_ARIA_ATTR: false});

// prohibit HTML5 data attributes, leave other safe HTML as is (default is true)
const clean = DOMPurify.sanitize(dirty, {ALLOW_DATA_ATTR: false});

// DOMPurify allows to define rules for Custom Elements. When using the CUSTOM_ELEMENT_HANDLING
// literal, it is possible to define exactly what elements you wish to allow (by default, none are allowed).
//
// The same goes for their attributes. By default, the built-in or configured allow.list is used.
//
// You can use a RegExp literal to specify what is allowed or a predicate, examples for both can be seen below.
// The default values are very restrictive to prevent accidental XSS bypasses. Handle with great care!

const clean = DOMPurify.sanitize(
    '<foo-bar baz="foobar" forbidden="true"></foo-bar><div is="foo-baz"></div>',
    {
        CUSTOM_ELEMENT_HANDLING: {
            tagNameCheck: null, // no custom elements are allowed
            attributeNameCheck: null, // default / standard attribute allow-list is used
            allowCustomizedBuiltInElements: false, // no customized built-ins allowed
        },
    }
); // <div is=""></div>

const clean = DOMPurify.sanitize(
    '<foo-bar baz="foobar" forbidden="true"></foo-bar><div is="foo-baz"></div>',
    {
        CUSTOM_ELEMENT_HANDLING: {
            tagNameCheck: /^foo-/, // allow all tags starting with "foo-"
            attributeNameCheck: /baz/, // allow all attributes containing "baz"
            allowCustomizedBuiltInElements: true, // customized built-ins are allowed
        },
    }
); // <foo-bar baz="foobar"></foo-bar><div is="foo-baz"></div>

const clean = DOMPurify.sanitize(
    '<foo-bar baz="foobar" forbidden="true"></foo-bar><div is="foo-baz"></div>',
    {
        CUSTOM_ELEMENT_HANDLING: {
            tagNameCheck: (tagName) => tagName.match(/^foo-/), // allow all tags starting with "foo-"
            attributeNameCheck: (attr) => attr.match(/baz/), // allow all containing "baz"
            allowCustomizedBuiltInElements: true, // allow customized built-ins
        },
    }
); // <foo-bar baz="foobar"></foo-bar><div is="foo-baz"></div>

// extend the existing array of elements that can use Data URIs
const clean = DOMPurify.sanitize(dirty, {ADD_DATA_URI_TAGS: ['a', 'area']});

// extend the existing array of elements that are safe for URI-like values (be careful, XSS risk)
const clean = DOMPurify.sanitize(dirty, {ADD_URI_SAFE_ATTR: ['my-attr']});

// allow external protocol handlers in URL attributes (default is false, be careful, XSS risk)
// by default only http, https, ftp, ftps, tel, mailto, callto, sms, cid and xmpp are allowed.
const clean = DOMPurify.sanitize(dirty, {ALLOW_UNKNOWN_PROTOCOLS: true});

// allow specific protocols handlers in URL attributes via regex (default is false, be careful, XSS risk)
// by default only http, https, ftp, ftps, tel, mailto, callto, sms, cid and xmpp are allowed.
// Default RegExp: /^(?:(?:(?:f|ht)tps?|mailto|tel|callto|sms|cid|xmpp):|[^a-z]|[a-z+.\-]+(?:[^a-z+.\-:]|$))/i;
const clean = DOMPurify.sanitize(dirty, {ALLOWED_URI_REGEXP: /^(?:(?:(?:f|ht)tps?|mailto|tel|callto|sms|cid|xmpp|xxx):|[^a-z]|[a-z+.\-]+(?:[^a-z+.\-:]|$))/i});

// return a DOM HTMLBodyElement instead of an HTML string (default is false)
const clean = DOMPurify.sanitize(dirty, {RETURN_DOM: true});

// return a DOM DocumentFragment instead of an HTML string (default is false)
const clean = DOMPurify.sanitize(dirty, {RETURN_DOM_FRAGMENT: true});

// use the RETURN_TRUSTED_TYPE flag to turn on Trusted Types support if available
const clean = DOMPurify.sanitize(dirty, {RETURN_TRUSTED_TYPE: true}); // will return a TrustedHTML object instead of a string if possible

// use a provided Trusted Types policy
const clean = DOMPurify.sanitize(dirty, {
    // supplied policy must define createHTML and createScriptURL
    TRUSTED_TYPES_POLICY: trustedTypes.createPolicy({
        createHTML(s) { return s},
        createScriptURL(s) { return s},
    }
});

// return entire document including <html> tags (default is false)
const clean = DOMPurify.sanitize(dirty, {WHOLE_DOCUMENT: true});

// disable DOM Clobbering protection on output (default is true, handle with care, minor XSS risks here)
const clean = DOMPurify.sanitize(dirty, {SANITIZE_DOM: false});

// enforce strict DOM Clobbering protection via namespace isolation (default is false)
// when enabled, isolates the namespace of named properties (i.e., `id` and `name` attributes)
// from JS variables by prefixing them with the string `user-content-`
const clean = DOMPurify.sanitize(dirty, {SANITIZE_NAMED_PROPS: true});

// keep an element's content when the element is removed (default is true)
const clean = DOMPurify.sanitize(dirty, {KEEP_CONTENT: false});

// glue elements like style, script or others to document.body and prevent unintuitive browser behavior in several edge-cases (default is false)
const clean = DOMPurify.sanitize(dirty, {FORCE_BODY: true});

// remove all <a> elements under <p> elements that are removed
const clean = DOMPurify.sanitize(dirty, {FORBID_CONTENTS: ['a'], FORBID_TAGS: ['p']});

// change the parser type so sanitized data is treated as XML and not as HTML, which is the default
const clean = DOMPurify.sanitize(dirty, {PARSER_MEDIA_TYPE: 'application/xhtml+xml'});

// use the IN_PLACE mode to sanitize a node "in place", which is much faster depending on how you use DOMPurify
const dirty = document.createElement('a');
dirty.setAttribute('href', 'javascript:alert(1)');

const clean = DOMPurify.sanitize(dirty, {IN_PLACE: true}); // see https://github.com/cure53/DOMPurify/issues/288 for more info

DOMPurify.addHook(
  'uponSanitizeAttribute',
  function (currentNode, hookEvent, config) {
    // Do something with the current node
    // You can also mutate hookEvent for current node (i.e. set hookEvent.forceKeepAttr = true)
    // For other than 'uponSanitizeAttribute' hook types hookEvent equals to null
  }
);

DOMPurify

DOMPurify

What does it do?

How do I use it?

Using the unminified development version

Using the minified and tested production version (source-map available)

Is there any foot-gun potential?

Okay, makes sense, let’s move on

Running DOMPurify on the server

Is there a demo?

What if I find a security bug?

Some purification samples please?

What is supported?

What about legacy browsers like Internet Explorer?

What about DOMPurify and Trusted Types?

Can I configure DOMPurify?

General settings

Control our allow-lists and block-lists

Control behavior relating to Custom Elements

Control behavior relating to URI values

Control permitted attribute values

Influence the return-type

Influence how we sanitize

Influence where we sanitize

Persistent Configuration

Hooks

Removed Configuration

Continuous Integration

Development and contributing

Installation (`npm i`)

Scripts

Security Mailing List

Who contributed?

Testing powered by

DOMPurify

DOMPurify

What does it do?

How do I use it?

Using the unminified development version

Using the minified and tested production version (source-map available)

Is there any foot-gun potential?

Okay, makes sense, let’s move on

Running DOMPurify on the server

Is there a demo?

What if I find a security bug?

Some purification samples please?

What is supported?

What about legacy browsers like Internet Explorer?

What about DOMPurify and Trusted Types?

Can I configure DOMPurify?

General settings

Control our allow-lists and block-lists

Control behavior relating to Custom Elements

Control behavior relating to URI values

Control permitted attribute values

Influence the return-type

Influence how we sanitize

Influence where we sanitize

Persistent Configuration

Hooks

Removed Configuration

Continuous Integration

Development and contributing

Installation (npm i)

Scripts

Security Mailing List

Who contributed?

Testing powered by

Installation (`npm i`)