Description
The Everest Forms plugin for WordPress is vulnerable to Server-Side Request Forgery in all versions up to, and including, 3.4.4. This is due to the `load_previous_field_value()` method in `class-evf-form-task.php` accepting arbitrary URL values from `$_POST` data for upload fields without domain restriction, which are then passed to `wp_remote_head()` in the `get_local_file_size()` method of `class-evf-form-fields-upload.php`. This makes it possible for unauthenticated attackers to force the WordPress server to make outbound HTTP HEAD requests to arbitrary URLs by submitting a form with an upload field containing a malicious URL while leaving a required field empty to trigger form re-rendering.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| wpeverest | Everest Forms – Contact Form, Payment Form, Quiz, Survey & Custom Form Builder with AI | ≤ 3.4.4 | — |
References
- https://www.wordfence.com/threat-intel/vulnerabilities/id/c5bbf7ed-c154-4153-adbf-59f0f7aa3a18?source=cve
- https://plugins.trac.wordpress.org/browser/everest-forms/trunk/includes/class-evf-form-task.php#L1448
- https://plugins.trac.wordpress.org/browser/everest-forms/trunk/includes/abstracts/class-evf-form-fields-upload.php#L1196
- https://plugins.trac.wordpress.org/changeset/3507814/