SureForms <= 1.13.1 - Cross-Site Request Forgery Protection Bypass via Improper Nonce Distribution

Vulnerability Description

The SureForms plugin for WordPress is vulnerable to Cross-Site Request Forgery Bypass in all versions up to, and including, 1.13.1. This is due to the plugin distributing generic WordPress REST API nonces (wp_rest) to unauthenticated users via the 'wp_ajax_nopriv_rest-nonce' action. While the plugin legitimately needs to support unauthenticated form submissions, it incorrectly uses generic REST nonces instead of form-specific nonces. This makes it possible for unauthenticated attackers to bypass CSRF protection on REST API endpoints that rely solely on nonce verification without additional authentication checks, allowing them to trigger unauthorized actions such as the plugin's own post-submission hooks and potentially other plugins' REST endpoints.

References

• https://www.wordfence.com/threat-intel/vulnerabilities/id/b083cf9d-bcfe-4234-a816-2d216da28b57?source=cve
• https://plugins.trac.wordpress.org/browser/sureforms/tags/1.13.1/inc/background-process.php#L74
• https://plugins.trac.wordpress.org/browser/sureforms/tags/1.13.1/inc/admin-ajax.php#L45
• https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&new=3391762%40sureforms%2Ftrunk&old=3382423%40sureforms%2Ftrunk&sfp_email=&sfph_mail=