CVE-2025-12826: Critical Authorization Bypass in Custom Post Type UI WordPress Plugin

Overview

CVE-2025-12826 is a medium-severity vulnerability affecting the Custom Post Type UI (CPT UI) plugin for WordPress. This vulnerability allows authenticated attackers, even those with minimal (subscriber-level) privileges, to add, edit, or delete custom post types under specific conditions. This is due to a lack of proper authorization checks within a key function of the plugin.

Published: 2025-12-04T07:16:14.920

Technical Details

The vulnerability resides in the cptui_process_post_type function within the Custom Post Type UI plugin. Versions up to and including 1.18.0 fail to adequately verify if a user possesses the necessary capability to perform actions such as creating, modifying, or deleting custom post types. As a result, an attacker with subscriber or higher privileges can bypass intended authorization restrictions and manipulate custom post types through crafted requests.

CVSS Analysis

The Common Vulnerability Scoring System (CVSS) assigns this vulnerability a score of 4.8, indicating a medium severity. This is based on the following factors:

• Attack Vector (AV): Network (N)
• Attack Complexity (AC): Low (L)
• Privileges Required (PR): Low (L)
• User Interaction (UI): None (N)
• Scope (S): Unchanged (U)
• Confidentiality Impact (C): None (N)
• Integrity Impact (I): Low (L)
• Availability Impact (A): None (N)

While confidentiality and availability are not affected, the potential for unauthorized modification of website content classifies this as a noteworthy risk.

Possible Impact

Successful exploitation of this vulnerability can lead to:

• Website Defacement: Attackers could create or modify custom post types to inject malicious content, leading to website defacement.
• SEO Poisoning: Unauthorized modification of custom post types could be used to inject spam content, harming the website’s search engine ranking.
• Data Manipulation: Depending on how custom post types are used, attackers might be able to manipulate data stored within those post types.

Mitigation and Patch Steps

The primary mitigation step is to update the Custom Post Type UI plugin to the latest version. The vulnerability has been addressed in versions newer than 1.18.0. Here’s how:

1. Log in to your WordPress administration dashboard.
2. Navigate to the “Plugins” section.
3. Locate the “Custom Post Type UI” plugin.
4. If an update is available, click the “Update Now” button.
5. Verify that the updated version is greater than 1.18.0.

If you cannot immediately update, consider temporarily disabling the plugin until an update can be performed.

References

• Custom Post Type UI Commit (GitHub)
• Wordfence Threat Intelligence Report