Summary
An authenticated, low-privilege user (able to create/edit forms) can inject arbitrary HTML/JS into the Craft Control Panel (CP) builder and integrations views. User-controlled form labels and integration metadata are rendered with dangerouslySetInnerHTML without sanitization, leading to stored XSS that executes when any admin views the builder/integration screens.
Affected Product - Ecosystem: Packagist (Craft CMS plugin) - Package: solspace/craft-freeform - Version: <= 5.14.6 (latest observed). Likely all 5.x until patched.
Details
- Root cause: Multiple user-controlled strings (field labels, section labels, integration icons, short names, WYSIWYG previews) are injected into React components using dangerouslySetInnerHTML without sanitization.
- Evidence: dangerouslySetInnerHTML on user-controlled properties in bundled CP JS at packages/plugin/src/Resources/js/client/client.js.
PoCs
- Label-based XSS:
1. In Craft CP, create/edit a Freeform field and set its label to <img src=x onerror="alert('xss-label')">.
2. Open the form builder view containing the field.
3. Alert executes (stored XSS).
- Integration icon SVG:
1. Set an integration "icon SVG" to <svg><script>alert('xss-icon')</script></svg>.
2. Open the integrations CP view.
3. Script executes.
Impact Arbitrary JS in admin CP; session/CSRF token theft; potential full admin takeover via DOM-driven actions.
Remediation
- Sanitize/HTML-encode all user-controlled strings before passing to dangerouslySetInnerHTML, or avoid it for labels/titles/icons.
- Server-side: strip/escape disallowed tags on save for fields, integration metadata, WYSIWYG content.
- Add regression tests with <img onerror> payloads to ensure no execution in builder/integration views.
Workarounds - Restrict form-edit permissions to trusted admins only until patched. - Consider CSP that disallows inline scripts (defense-in-depth only).
Credits - Discovered by https://www.linkedin.com/in/praveenkavinda/ | Prav33N-Sec.
{
"cwe_ids": [
"CWE-79"
],
"github_reviewed_at": "2026-01-22T21:41:14Z",
"nvd_published_at": "2026-02-12T23:16:09Z",
"github_reviewed": true,
"severity": "LOW"
}