CVE-2026-2504: WordPress Dealia Auth Bypass Vulnerability

CVE-2026-2504 Overview

The Dealia – Request a quote plugin for WordPress contains a missing authorization vulnerability that allows authenticated attackers with Contributor-level access or above to perform unauthorized modifications to plugin configuration. The vulnerability exists because the plugin exposes the admin nonce (DEALIA_ADMIN_NONCE) to all users with edit_posts capability via wp_localize_script() in PostsController.php, while the AJAX handlers in AdminSettingsController.php only verify the nonce without checking current_user_can('manage_options').

Critical Impact

Authenticated attackers with low-privilege Contributor roles can reset plugin configuration, potentially disrupting business functionality and quote request workflows.

Affected Products

• Dealia – Request a quote plugin for WordPress versions up to and including 1.0.6

Discovery Timeline

• 2026-02-19 - CVE CVE-2026-2504 published to NVD
• 2026-02-19 - Last updated in NVD database

Technical Details for CVE-2026-2504

Vulnerability Analysis

This vulnerability is classified as CWE-862 (Missing Authorization). The fundamental security flaw stems from the plugin's improper separation between nonce verification and capability checking. WordPress nonces are designed to protect against CSRF attacks by validating that requests originate from legitimate forms, but they are not intended to serve as authorization controls. The plugin incorrectly relies solely on nonce verification for administrative AJAX actions without implementing proper capability checks.

The PostsController.php file exposes the DEALIA_ADMIN_NONCE to users with edit_posts capability, which includes Contributors and above. This nonce is then used by multiple AJAX handlers in AdminSettingsController.php at lines 243, 309, and 416. Since these handlers only verify the nonce without calling current_user_can('manage_options'), any authenticated user with access to the nonce can invoke administrative functions.

Root Cause

The root cause is the improper implementation of authorization controls in the plugin's AJAX handlers. The developers incorrectly assumed that nonce verification would provide sufficient access control. However, since the nonce is exposed to lower-privileged users through wp_localize_script(), the authorization boundary is effectively bypassed. The missing current_user_can('manage_options') check in AdminSettingsController.php allows any authenticated user with the nonce to execute privileged administrative actions.

Attack Vector

The attack is network-based and requires low privileges (Contributor-level access). An attacker must first authenticate to the WordPress site with at least Contributor-level credentials. Upon authentication, the attacker gains access to the DEALIA_ADMIN_NONCE value exposed via the localized script. The attacker can then craft malicious AJAX requests to the vulnerable handlers in AdminSettingsController.php, bypassing the intended administrative restrictions. This allows the attacker to reset plugin configuration, potentially disrupting the quote request functionality.

The vulnerability is exploited by capturing the admin nonce from the page source and submitting crafted AJAX requests to the vulnerable endpoints. The AJAX handlers at lines 243, 309, and 416 of AdminSettingsController.php process these requests without verifying that the user has administrative capabilities. Technical details can be found in the Wordfence Vulnerability Analysis and the WordPress Plugin Trac repository.

Detection Methods for CVE-2026-2504

Indicators of Compromise

• Unexpected changes to Dealia plugin settings or configuration resets
• AJAX requests to Dealia admin endpoints from non-administrator user accounts
• Log entries showing administrative actions performed by Contributor-level users
• Unusual activity patterns from accounts with edit_posts capability targeting plugin AJAX handlers

Detection Strategies

• Monitor WordPress AJAX requests to AdminSettingsController.php endpoints for requests from non-administrator users
• Implement logging for plugin configuration changes and correlate with user capability levels
• Review web server access logs for patterns of AJAX calls to Dealia plugin endpoints from users without manage_options capability
• Deploy Web Application Firewall (WAF) rules to detect unauthorized AJAX requests to vulnerable endpoints

Monitoring Recommendations

• Enable detailed WordPress audit logging to track plugin configuration changes
• Configure alerts for configuration modifications performed by users below Administrator role
• Monitor for bulk or automated AJAX requests targeting Dealia plugin endpoints
• Implement real-time detection for unauthorized administrative actions through security plugins

How to Mitigate CVE-2026-2504

Immediate Actions Required

• Update the Dealia – Request a quote plugin to the latest patched version immediately
• Review recent plugin configuration changes and restore from backup if unauthorized modifications are detected
• Audit Contributor-level accounts for suspicious activity
• Temporarily restrict Contributor account access if a patch is not yet available

Patch Information

Check the WordPress plugin repository for an updated version of the Dealia – Request a quote plugin that addresses this vulnerability. The fix should implement proper current_user_can('manage_options') checks in all AJAX handlers within AdminSettingsController.php. Monitor the WordPress Plugin Trac for updates to the trunk version.

Workarounds

• If unable to update immediately, consider temporarily deactivating the Dealia plugin until a patch is available
• Restrict or remove Contributor-level accounts that do not require access
• Implement additional access controls at the web server level to restrict access to plugin AJAX endpoints
• Use a WordPress security plugin to add capability checks for vulnerable AJAX actions

# Configuration example - Restrict access to plugin AJAX handlers via .htaccess
# Add to WordPress .htaccess file
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{REQUEST_URI} ^.*admin-ajax\.php$ [NC]
RewriteCond %{QUERY_STRING} action=dealia_admin [NC]
RewriteCond %{HTTP_COOKIE} !wordpress_logged_in.*administrator [NC]
RewriteRule .* - [F,L]
</IfModule>