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:
- In Craft CP, create/edit a Freeform field and set its label to
<img src=x onerror="alert('xss-label')">.
- Open the form builder view containing the field.
- Alert executes (stored XSS).
- Integration icon SVG:
- Set an integration "icon SVG" to
<svg><script>alert('xss-icon')</script></svg>.
- Open the integrations CP view.
- 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
Disclosure / CVE Request
- Request CVE for this confirmed stored XSS.
References
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
dangerouslySetInnerHTMLwithout sanitization, leading to stored XSS that executes when any admin views the builder/integration screens.Affected Product
Details
dangerouslySetInnerHTMLwithout sanitization.dangerouslySetInnerHTMLon user-controlled properties in bundled CP JS at packages/plugin/src/Resources/js/client/client.js.PoCs
<img src=x onerror="alert('xss-label')">.<svg><script>alert('xss-icon')</script></svg>.Impact
Arbitrary JS in admin CP; session/CSRF token theft; potential full admin takeover via DOM-driven actions.
Remediation
dangerouslySetInnerHTML, or avoid it for labels/titles/icons.<img onerror>payloads to ensure no execution in builder/integration views.Workarounds
Credits
Disclosure / CVE Request
References