GHSA-mx4q-xxc9-pf5q
MEDIUMSylius Vulnerable to Authenticated Stored XSS
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
sylius/sylius🐘sylius/sylius🐘sylius/syliusReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Impact
An authenticated stored cross-site scripting (XSS) vulnerability exists in multiple places across the shop frontend and admin panel due to unsanitized entity names being rendered as raw HTML.
Shop breadcrumbs (shared/breadcrumbs.html.twig): The breadcrumbs macro uses the Twig |raw filter on label values. Since taxon names, product names, and ancestor names flow directly into these labels, a malicious taxon name like <img src=x onerror=alert('XSS')> is rendered and executed as JavaScript on the storefront.
Admin product taxon picker (ProductTaxonTreeController.js): The rowRenderer method interpolates ${name} directly into a template literal building HTML, allowing script injection through taxon names in the admin panel.
Admin autocomplete fields (Tom Select): Dropdown items and options render entity names as raw HTML without escaping, allowing XSS through any autocomplete field displaying entity names.
An authenticated administrator can inject arbitrary HTML or JavaScript via entity names (e.g. taxon name) that is persistently rendered for all users.
Patches
The issue is fixed in versions: 2.0.16, 2.1.12, 2.2.3 and above.
Workarounds
Override vulnerable templates and JavaScript controllers at the project level.
Step 1 — Override shop breadcrumbs template
templates/bundles/SyliusShopBundle/shared/breadcrumbs.html.twig:
{% macro breadcrumbs(items) %}
<ol class="breadcrumb" aria-label="breadcrumbs">
{% for item in items %}
<li class="breadcrumb-item fw-normal{{ item.active is defined and item.active ? ' active' }}">
{% if item.path is defined %}
<a class="link-reset" href="{{ item.path }}" {{ item.test_attribute is defined ? sylius_test_html_attribute(item.test_attribute) }}>{{ item.label }}</a>
{% else %}
<span class="text-body-tertiary text-break" {{ item.test_attribute is defined ? sylius_test_html_attribute(item.test_attribute) }}>{{ item.label }}</span>
{% endif %}
</li>
{% endfor %}
</ol>
{% endmacro %}
Step 2 — Override order breadcrumbs template
templates/bundles/SyliusShopBundle/account/order/show/content/breadcrumbs.html.twig:
{% from '@SyliusShop/shared/breadcrumbs.html.twig' import breadcrumbs as breadcrumbs %}
{% set order = hookable_metadata.context.order %}
<div class="col-12">
{{ breadcrumbs([
{ label: 'sylius.ui.home'|trans, path: path('sylius_shop_homepage')},
{ label: 'sylius.ui.my_account'|trans, path: path('sylius_shop_account_dashboard')},
{ label: 'sylius.ui.order_history'|trans, path: path('sylius_shop_account_order_index')},
{ label: '#'~order.number, active: true, test_attribute: 'order-number' }
]) }}
</div>
Step 3 — Override ProductTaxonTreeController.js
Disable the vendor controller in assets/admin/controllers.json:
"product-taxon-tree": {
- "enabled": true,
+ "enabled": false,
"fetch": "lazy"
},
Create assets/admin/controllers/product_taxon_tree_controller.js — copy the original from vendor/sylius/sylius/src/Sylius/Bundle/AdminBundle/Resources/assets/controllers/ProductTaxonTreeController.js and apply the following change:
+ const escapeHtml = (str) => {
+ const div = document.createElement('div');
+ div.textContent = str;
+ return div.innerHTML;
+ };
// in rowRenderer:
- <span class="infinite-tree-title">${name}</span>
+ <span class="infinite-tree-title">${escapeHtml(name)}</span>
Register the patched controller in assets/admin/bootstrap.js:
import ProductTaxonTreeController from './controllers/product_taxon_tree_controller';
app.register('sylius--admin-bundle--product-taxon-tree', ProductTaxonTreeController);
Step 4 — Add autocomplete XSS protection
assets/admin/scripts/autocomplete-xss-protection.js:
const escapeHtml = (str) => {
if (typeof str !== 'string') return str;
const div = document.createElement('div');
div.textContent = str;
return div.innerHTML;
};
document.addEventListener('autocomplete:pre-connect', (event) => {
const options = event.detail.options;
if (!options.render) return;
const labelField = options.labelField || 'text';
const wrapRenderer = (renderer) => {
if (!renderer) return renderer;
return (data, escape) => {
const escaped = { ...data };
if (escaped[labelField]) {
escaped[labelField] = escapeHtml(escaped[labelField]);
}
return renderer(escaped, escape);
};
};
if (options.render.item) options.render.item = wrapRenderer(options.render.item);
if (options.render.option) options.render.option = wrapRenderer(options.render.option);
});
Import in assets/admin/entrypoint.js before bootstrap:
+ import './scripts/autocomplete-xss-protection';
import './bootstrap.js';
Step 5 — Rebuild assets
yarn encore dev # or: yarn encore production
Reporters
We would like to extend our gratitude to the following individuals for their detailed reporting and responsible disclosure of this vulnerability:
- Djibril Mounkoro (@whiteov3rflow)
- Bartłomiej Nowiński (@bnBart)
For more information
If you have any questions or comments about this advisory:
- Open an issue in Sylius issues
- Email us at [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | sylius/sylius | ≥ 2.0.0&&< 2.0.16 | 2.0.16 |
| 🐘Packagist | sylius/sylius | ≥ 2.1.0&&< 2.1.12 | 2.1.12 |
| 🐘Packagist | sylius/sylius | ≥ 2.2.0&&< 2.2.3 | 2.2.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for sylius/sylius. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update sylius/sylius to 2.0.16 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mx4q-xxc9-pf5q is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-mx4q-xxc9-pf5q is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-mx4q-xxc9-pf5q. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-mx4q-xxc9-pf5q in your dependencies?
O3 detects GHSA-mx4q-xxc9-pf5q across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.