CVE-2026-25368: Calculated Fields Form Auth Bypass Flaw

CVE-2026-25368 Overview

A Missing Authorization vulnerability has been identified in the codepeople Calculated Fields Form WordPress plugin. This security flaw allows attackers to exploit incorrectly configured access control security levels, potentially leading to unauthorized access to sensitive form data and configurations. The vulnerability stems from a Broken Access Control weakness (CWE-862) that fails to properly validate user permissions before granting access to protected resources.

Critical Impact

Authenticated attackers with low privileges can bypass authorization controls to access confidential information stored within Calculated Fields Form configurations, potentially exposing sensitive business data and form submissions.

Affected Products

• Calculated Fields Form WordPress plugin versions up to and including 5.4.4.1
• WordPress installations using vulnerable versions of the calculated-fields-form plugin
• Sites utilizing Calculated Fields Form for data collection and processing

Discovery Timeline

• 2026-02-19 - CVE-2026-25368 published to NVD
• 2026-02-19 - Last updated in NVD database

Technical Details for CVE-2026-25368

Vulnerability Analysis

This Missing Authorization vulnerability represents a fundamental access control failure within the Calculated Fields Form plugin. The plugin fails to implement proper capability checks on certain endpoints or functions, allowing authenticated users with minimal privileges to access resources that should be restricted to administrators or higher-privileged roles.

The vulnerability falls under CWE-862 (Missing Authorization), which occurs when software does not perform authorization checks when an actor attempts to access a resource or perform an action. In WordPress plugin contexts, this typically manifests when AJAX handlers, REST API endpoints, or administrative functions lack proper current_user_can() checks or equivalent authorization mechanisms.

The network-based attack vector requires only low-level authentication (such as a subscriber account) with no user interaction needed, making exploitation relatively straightforward for attackers who can obtain any authenticated session.

Root Cause

The root cause of this vulnerability is the absence of proper authorization checks within the Calculated Fields Form plugin's code. When handling requests to access form data, configurations, or administrative functions, the plugin fails to verify that the requesting user has the appropriate WordPress capabilities. This allows any authenticated user, regardless of their assigned role, to access functionality intended only for administrators.

Attack Vector

The attack is network-based and requires an authenticated session with minimal privileges. An attacker would need to:

1. Obtain authentication to the target WordPress site (even as a low-privileged subscriber)
2. Identify and access the vulnerable endpoints or AJAX handlers within the Calculated Fields Form plugin
3. Bypass the missing authorization checks to access protected resources
4. Extract confidential form configurations, submitted data, or other sensitive information

The vulnerability allows unauthorized information disclosure without requiring any user interaction, making it particularly dangerous in environments where untrusted users have authenticated access.

Detection Methods for CVE-2026-25368

Indicators of Compromise

• Unexpected access to Calculated Fields Form administrative endpoints by non-admin users
• Anomalous AJAX requests to plugin endpoints from low-privileged user sessions
• Access logs showing subscriber or contributor-level users accessing form configuration data
• Unauthorized retrieval of form submission data or field configurations

Detection Strategies

• Monitor WordPress access logs for requests to /wp-admin/admin-ajax.php with Calculated Fields Form action parameters from non-administrative users
• Implement user activity monitoring plugins to track access patterns to plugin functionality
• Review server logs for unusual patterns of requests to the calculated-fields-form plugin directory
• Deploy Web Application Firewall (WAF) rules to detect and alert on broken access control attempts

Monitoring Recommendations

• Enable detailed logging for WordPress AJAX actions and REST API endpoints
• Implement real-time alerting for access control anomalies involving the Calculated Fields Form plugin
• Conduct periodic access control audits of all installed WordPress plugins
• Monitor for newly created or modified user accounts that could indicate attackers establishing persistent access

How to Mitigate CVE-2026-25368

Immediate Actions Required

• Update the Calculated Fields Form plugin to a version newer than 5.4.4.1 as soon as a patched version is available
• Review WordPress user accounts and remove or restrict any unnecessary authenticated users
• Implement additional access control measures using security plugins until a patch is applied
• Audit recent access logs to identify any potential exploitation attempts

Patch Information

Organizations should monitor the official Calculated Fields Form plugin page and the Patchstack Vulnerability Report for patch availability. Update to the latest patched version immediately once released by the vendor. Ensure automatic plugin updates are enabled or establish a rapid deployment process for security patches.

Workarounds

• Restrict WordPress user registration and minimize the number of authenticated users with access to the site
• Implement IP-based access restrictions for administrative functions using .htaccess or server-level configurations
• Deploy a Web Application Firewall (WAF) to filter and monitor requests to vulnerable plugin endpoints
• Consider temporarily disabling the Calculated Fields Form plugin if it is not critical to operations until a patch is available
• Use WordPress capability management plugins to further restrict subscriber and contributor permissions

# Configuration example - Restrict access to wp-admin AJAX for non-admin users via .htaccess
# Add to WordPress root .htaccess file

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{REQUEST_URI} ^/wp-admin/admin-ajax\.php
RewriteCond %{HTTP_COOKIE} !wordpress_logged_in.*administrator [NC]
RewriteCond %{QUERY_STRING} action=.*calculated.*fields [NC]
RewriteRule .* - [F,L]
</IfModule>