https://github.com/aegisjsproject/sanitizer
Sanitizer API polyfill & config
https://github.com/aegisjsproject/sanitizer
aegis sanitizer sanitizer-api security
Last synced: 6 months ago
JSON representation
Sanitizer API polyfill & config
- Host: GitHub
- URL: https://github.com/aegisjsproject/sanitizer
- Owner: AegisJSProject
- License: mit
- Created: 2024-03-07T19:06:37.000Z (over 1 year ago)
- Default Branch: master
- Last Pushed: 2025-04-10T17:03:57.000Z (6 months ago)
- Last Synced: 2025-04-13T09:08:38.581Z (6 months ago)
- Topics: aegis, sanitizer, sanitizer-api, security
- Language: JavaScript
- Homepage: https://www.npmjs.com/package/@aegisjsproject/sanitizer
- Size: 790 KB
- Stars: 2
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- Contributing: .github/CONTRIBUTING.md
- Funding: .github/FUNDING.yml
- License: LICENSE
- Code of conduct: .github/CODE_OF_CONDUCT.md
- Codeowners: .github/CODEOWNERS
Awesome Lists containing this project
README
# `@aegisjsproject/sanitizer`
[Sanitizer API](https://github.com/WICG/sanitizer-api/) polyfill & config
[](https://github.com/AegisJSProject/sanitizer/actions/workflows/codeql-analysis.yml)

[](https://github.com/AegisJSProject/sanitizer/blob/master/LICENSE)
[](https://github.com/AegisJSProject/sanitizer/commits/master)
[](https://github.com/AegisJSProject/sanitizer/releases)
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- - -- [Code of Conduct](./.github/CODE_OF_CONDUCT.md)
- [Contributing](./.github/CONTRIBUTING.md)## AegisJSProject Sanitizer
This is a library & polyfill for the [Sanitizer API](https://github.com/WICG/sanitizer-api/).
It provides a minimal polyfill for `Element.prototype.setHTML()` & `Document.parseHTML()`,
as well as config files for HTML, SVG, & MathML. Please note, however, that the
default sanitizer config in these sanitizer methods *only* support HTML by default.The "base" config (not what is used by default) *DOES* add support for ``,
and the "complete" config supports `` & ``.This helps prevent XSS via:
- Stripping event attributes such as `onclick`
- Removing unsafe URL attributes such a ``
- Prevents adding ``s and `<style>`s
- Removes other potentially dangerous elements & attributes### Example
```js
import '@aegijsproject/sanitizer/polyfill.js';
import { sanitizer } from '@aegisjsproject/sanitizer/config/base.js';document.body.setHTML(`
<header id="header">
<h1 onclick="alert(location.href)" data-foo="bar">Hello, World!</h1>
</header>
<nav id="nav" class="flex row">
<button type="button" popovertarget="bacon" popovertargetaction="show" accesskey="b">Show Bacon Ipsum</button>
<a href="#foo">Normal Link</a>
<a href="javascript:alert('javascript:')"><code>javascript:</code> Link</a>
<a href="data:text/plain,Not%20Allowed" target="_blank"><code>data:</code> Link</a>
<a href="${URL.createObjectURL(file)}" target="_blank"><code>blob:</code> Link</a>
</nav>
<main id="main"></main>
<div popover="auto" id="bacon">
<div>
<b>Bacon Ipsum</b>
<button type="button" popovertarget="bacon" popovertargetaction="hide">
<svg xmlns="http://www.w3.org/2000/svg" width="12" height="16" viewBox="0 0 12 16" fill="currentColor" role="presentation" aria-label="Close Popover">
<path fill-rule="evenodd" d="M7.48 8l3.75 3.75-1.48 1.48L6 9.48l-3.75 3.75-1.48-1.48L4.52 8 .77 4.25l1.48-1.48L6 6.52l3.75-3.75 1.48 1.48L7.48 8z"/>
</svg>
</button>
</div>
<p>Bacon ipsum dolor amet pork belly frankfurter drumstick jowl brisket capicola
short ribs.Cow chislic ham hock t-bone shoulder salami rump corned beef spare
ribs prosciutto bresaola picanha drumstick. Swine tail pork belly ribeye beef
kielbasa. Beef cupim ball tip pastrami spare ribs strip steak tongue salam
venison. Venison cupim meatball strip steak meatloaf prosciutto buffalo
frankfurter hamburger flank boudin.</p>
</div>
`, sanitizer);
```### Restricting Allowed Content (eg for comments)
```js
const sanitizer = {
elements: ['span', 'div', 'p', 'code', 'pre', 'blockquote', 'img', 'a'],
attributes: ['href', 'src', 'loading', 'height', 'width', 'class', 'alt', 'target'],
};fetch('https://api.example.com/comments')
.then(resp => resp.json())
.then(comments => {
document.querySelector('.comments').append(...comments.map(comment => {
const el = document.createElement('div');
el.setHTML(comment.body, sanitizer);
return el;
}));
});
```### Adding to allowed elements / attributes
```js
import { elements, attributes } from '@aegisjsproject/sanitizer/config/html.js';const sanitizer = {
elements: ['hello-world', ...elements],
attributes: ['foo', ...attributes],
};document.querySelector('.container').setHTML(`
<hello-world foo="bar"></hello-world>
`, sanitizer);
```### Enforce Sanitization by default (on eg `innerHTML`, where supported)
```js
if ('trustedTypes' in globalThis) {
trustedTypes.createPolicy('default', {
createHTML(input) {
const el = document.createElement('div');
el.setHTML(input);
return el.innerHTML;
}
});
}
```