CVE-2026-13355: Meta Box AIO <= 3.11.0 And Standalone Plugin Extensions - Unauthenticated Privilege Escalation to Administrator to 'rwmb_frontend_field_object_id' Parameter
The Meta Box AIO plugin for WordPress is vulnerable to Privilege Escalation to Administrator in versions up to, and including, 3.11.0. This is due to a chained flaw: the populateviaquerystring() function in the mb-frontend-submission component unconditionally overrides the form's target objectid from the GET parameter 'rwmbfrontendfieldobjectid' without any authorization check, and Form::process() lacks the usercanedit() check present in render(), allowing unauthenticated attackers to overwrite the postcontent of any page with an arbitrary shortcode via wpupdatepost(); the mb-user-profile component then directly trusts the 'role' and 'autologin' shortcode attributes in the injected [mbuserprofileregister] shortcode with no role validation. This makes it possible for unauthenticated attackers to elevate their privileges to Administrator. The standalone plugins Meta Box Frontend Submission (in versions up to 4.5.6) and Meta Box User Profile (versions up to 3.11.0) are also affected.
Affected Software
Event History
Frequently Asked Questions
Does exploitation require an existing WordPress account or user interaction?
No. The vulnerability can be exploited by an unauthenticated attacker and does not require user interaction.
Which installations should be treated as affected?
Meta Box AIO versions up to and including 3.11.0 are affected. The standalone Meta Box Frontend Submission plugin through 4.5.6 and Meta Box User Profile plugin through 3.11.0 are also affected.
What should defenders look for when assessing potential exploitation?
The exploit chain overwrites page post content with an attacker-controlled shortcode, specifically leveraging the mb_user_profile_register shortcode attributes role and auto_login. Successful exploitation can result in creation or elevation of an Administrator-level account.