๐Ÿ” CVE Alert

CVE-2026-2839

MEDIUM 5.3

Advanced Custom Fields: Extended <= 0.9.2.7 - Missing Authorization to Unauthenticated Data Exposure via Multiple AJAX Endpoints

CVSS Score
5.3
EPSS Score
0.3%
EPSS Percentile
20th

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.

CWE CWE-862
Vendor hwk-fr
Product advanced custom fields: extended
Published Oct 28, 2026
Last Updated Oct 29, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability

Affected Versions

hwk-fr / Advanced Custom Fields: Extended
0 โ‰ค 0.9.2.7

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
wordfence.com: https://www.wordfence.com/threat-intel/vulnerabilities/id/9954ef37-bae0-48fb-9654-ff54750c46c2?source=cve 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#L24 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/changeset/3516027/ plugins.trac.wordpress.org: https://plugins.trac.wordpress.org/changeset/3754818/

Credits

Jay