CVE-2026-2839
Description
The Advanced Custom Fields: Extended plugin for WordPress is vulnerable to unauthorized access of data and triggering of server-side actions in all versions up to, and including, 0.9.2.7. This is due to multiple AJAX handlers registered for unauthenticated users (`wp_ajax_nopriv_*`) that fail to implement proper `current_user_can()` authorization checks. While these handlers use ACF's `acf_verify_ajax()` function to validate cryptographic nonces, the `acf_nonce` values are generated for guest users and publicly exposed in the page source of any frontend page utilizing an ACF form. This makes it possible for unauthenticated attackers to extract the guest nonce and bypass WordPress visibility permissions, leading to the unauthorized disclosure of post titles and internal Flexible Content layout structures. The vulnerability was partially patched in version 0.9.2.4.
Affected WordPress components
-
Advanced Custom Fields: Extended Plugin · acf-extendedUp to and including 0.9.2.7View on WordPress.org
A confirmed match is backed by the plugin or theme slug. A possible match is based on the product name only and should be verified.
Affected products and versions
- hwk-fr Advanced Custom Fields: Extended — Up to and including 0.9.2.7
References
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/acf-extended/trunk/includes/fields/field-advanced-link.php#L25
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/acf-extended/trunk/includes/fields/field-advanced-link.php#L603
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/acf-extended/trunk/includes/fields/field-flexible-content-async.php#L151
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/acf-extended/trunk/includes/fields/field-flexible-content-async.php#L24
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/changeset/3516027/
- plugins.trac.wordpress.org https://plugins.trac.wordpress.org/changeset/3754818/
- www.wordfence.com https://www.wordfence.com/threat-intel/vulnerabilities/id/9954ef37-bae0-48fb-9654-ff54750c46c2?source=cve
- nvd.nist.gov Official NVD record