CVE-2026-1930: Emailchef WordPress Auth Bypass Flaw

CVE-2026-1930 Overview

The Emailchef plugin for WordPress contains a missing capability check vulnerability in the page_options_ajax_disconnect() function affecting all versions up to and including 3.5.1. This authorization bypass vulnerability (CWE-862) enables authenticated attackers with Subscriber-level access or higher to delete the plugin's settings via the emailchef_disconnect AJAX action without proper authorization checks.

Critical Impact

Authenticated users with minimal privileges can reset the Emailchef plugin configuration, potentially disrupting email marketing integrations and causing service interruptions for WordPress sites using this email automation tool.

Affected Products

• Emailchef WordPress Plugin versions up to and including 3.5.1
• WordPress sites with registered Subscriber-level users or higher

Discovery Timeline

• April 22, 2026 - CVE-2026-1930 published to NVD
• April 22, 2026 - Last updated in NVD database

Technical Details for CVE-2026-1930

Vulnerability Analysis

This vulnerability represents a classic broken access control flaw where the page_options_ajax_disconnect() function lacks proper capability verification before executing privileged operations. The function handles the emailchef_disconnect AJAX action, which is designed to disconnect the Emailchef integration and delete associated plugin settings.

In WordPress, AJAX handlers must implement capability checks using functions like current_user_can() to verify that the requesting user has appropriate permissions. Without this check, any authenticated user—including those with minimal Subscriber privileges—can invoke the action. The vulnerability allows unauthorized data modification, specifically the deletion of plugin configuration settings that would typically require administrator-level access.

Root Cause

The root cause is a missing authorization check (CWE-862: Missing Authorization) in the AJAX handler function. The vulnerable code at line 121 and line 200 of class-emailchef-admin.php processes the disconnect request without first validating that the current user has administrative capabilities. The function processes the emailchef_disconnect action for any authenticated user who can trigger WordPress AJAX requests.

Attack Vector

An attacker needs only a valid WordPress account with Subscriber-level access—the lowest authenticated user role. The attack is executed over the network via an AJAX POST request to the WordPress admin-ajax endpoint with the action parameter set to emailchef_disconnect. No user interaction is required beyond authentication, and the attacker can directly target the vulnerable endpoint.

The attack flow involves the authenticated attacker sending a crafted AJAX request to /wp-admin/admin-ajax.php with the action parameter set to emailchef_disconnect. This triggers the vulnerable page_options_ajax_disconnect() function, which processes the request and deletes the plugin's configuration settings without verifying administrative privileges.

Detection Methods for CVE-2026-1930

Indicators of Compromise

• Unexpected AJAX requests to admin-ajax.php with the emailchef_disconnect action from non-administrator accounts
• Plugin settings being reset or cleared without administrator action
• Emailchef integration disconnections occurring unexpectedly
• Log entries showing Subscriber or Contributor-level users accessing plugin administrative AJAX endpoints

Detection Strategies

• Monitor WordPress AJAX request logs for the emailchef_disconnect action being invoked by non-administrative users
• Implement file integrity monitoring on the Emailchef plugin files, particularly class-emailchef-admin.php
• Review WordPress user activity logs for suspicious Subscriber account behavior targeting administrative functions
• Deploy web application firewall (WAF) rules to flag unauthorized AJAX action attempts

Monitoring Recommendations

• Enable detailed WordPress access logging including AJAX request parameters and user context
• Configure alerting for plugin configuration changes occurring outside expected administrative sessions
• Monitor for bulk or automated requests to the admin-ajax.php endpoint from authenticated low-privilege accounts
• Implement anomaly detection for Subscriber accounts attempting administrative plugin operations

How to Mitigate CVE-2026-1930

Immediate Actions Required

• Update the Emailchef plugin to a version newer than 3.5.1 that includes the security fix
• Review WordPress user accounts and remove unnecessary Subscriber registrations
• Audit recent plugin activity for signs of unauthorized configuration changes
• Temporarily disable the Emailchef plugin if an immediate update is not possible

Patch Information

A security patch has been released addressing this vulnerability. The fix adds proper capability checks to the page_options_ajax_disconnect() function before processing the disconnect request. Details of the code changes can be reviewed in the WordPress EmailChef Changeset Update. The patched version properly validates user capabilities before executing privileged operations. For additional vulnerability intelligence, see the Wordfence Vulnerability Intel Entry.

Workarounds

• Restrict user registration on WordPress sites to prevent unauthorized Subscriber account creation
• Implement additional authentication layers for administrative plugin functions using security plugins
• Use a web application firewall (WAF) to filter and block unauthorized AJAX requests targeting the emailchef_disconnect action
• Consider temporarily disabling the vulnerable plugin until an official patch can be applied

# Disable user registration to prevent new Subscriber accounts
# Add to wp-config.php
define('WP_ALLOW_USER_REGISTRATION', false);

# Alternatively, use WP-CLI to deactivate the plugin temporarily
wp plugin deactivate emailchef