GHSA-9f5h-mmq6-2x78

Craft CMS Vulnerable to Stored XSS in Number Prefix & Suffix Fields

## Summary A stored XSS vulnerability exists in the Number field type settings. The Prefix and Suffix fields are rendered using the `|md|raw` Twig filter without proper escaping, allowing script execution when the Number field is displayed on users' profiles. ## Proof of Concept ### Required Permissions - Administrator access - `allowAdminChanges` is enabled in production, which is against our [security recommendations](https://craftcms.com/knowledge-base/securing-craft). ### Steps to Reproduce 1. Log in with an admin account 2. Navigate to **Settings** → **Fields** → **New field** 3. Choose **Number** as the field type 4. Set the **Prefix/Suffix Text** field to: <img width="611" height="908" alt="image" src="https://github.com/user-attachments/assets/63766ca4-4fa9-490b-8bea-37364137527d" /> ```html <img src=x onerror="alert('Number Prefix/Suffix XSS')" hidden> ``` 5. Save the field 6. Add this field to any element (e.g., User Profile fields via **Settings** → **Users** → **User Fields**) 7. Navigate to your account (`/admin/myaccount`) or any user profile (`/admin/users/{id}`) 8. XSS executes when viewing the form <img width="1246" height="677" alt="image-1" src="https://github.com/user-attachments/assets/dafeb2b7-905f-4a4b-b3d6-1c16a905498f" /> ## Mitigation Sanitize prefix/suffix before rendering or use `|e` filter instead of `|raw`.