Attack Chain

1. Unauthenticated attacker registers a new user account on the WordPress site via a public registration form (e.g., ’new_user’ form). This account is assigned the ’editor’ role.
2. Attacker crafts a POST request to wp-admin/post.php to create a new ‘admin_form’ custom post type.
3. The POST request includes data that configures the form to be an ’edit_user’ form.
4. The attacker manipulates the POST data to include ‘administrator’ within the ‘role_options’ array for the form, bypassing UI restrictions.
5. Attacker submits the crafted POST request to create the malicious ’edit_user’ form.
6. Attacker crafts a new POST request, this time submitting data to the newly created ’edit_user’ form, targeting their own user ID.
7. The ‘pre_update_value()’ function validates the submitted role against the form’s ‘role_options’, but lacks permission checks, allowing the ‘administrator’ role to be assigned.
8. The attacker’s user account is successfully elevated to ‘administrator’ privileges.

Impact

Successful exploitation of CVE-2026-6228 allows an unauthenticated attacker to gain full administrative control over the affected WordPress site. This can lead to complete compromise, including data theft, defacement, malware injection, and denial of service. The CVSS v3.1 base score for this vulnerability is 8.8, indicating a high level of severity.

Recommendation

• Apply the patch or upgrade to a version of the Frontend Admin by DynamiApps plugin for WordPress greater than 3.28.36 to remediate CVE-2026-6228.
• Deploy the Sigma rule “Detect WordPress Frontend Admin Plugin Privilege Escalation Attempt” to monitor for suspicious POST requests to wp-admin/post.php attempting to manipulate the role_options array.
• Review WordPress user roles and permissions, ensuring that editor-level users do not have excessive capabilities, especially related to form creation and editing.