CVE-2026-27390: WeDesignTech Booking Auth Bypass Flaw

CVE-2026-27390 Overview

CVE-2026-27390 is an authentication bypass vulnerability in the designthemes WeDesignTech Ultimate Booking Addon plugin for WordPress. The flaw affects all versions up to and including 1.0.1. The vulnerability allows attackers to abuse authentication mechanisms through an alternate path or channel [CWE-288], leading to account takeover. Patchstack tracks this issue as an account takeover vulnerability. An attacker with low privileges can leverage the bypass over the network without user interaction. Successful exploitation results in full compromise of confidentiality, integrity, and availability of affected WordPress installations.

Critical Impact
Authenticated attackers with minimal privileges can take over arbitrary accounts, including administrative accounts, on WordPress sites running vulnerable versions of the plugin.

Affected Products

designthemes WeDesignTech Ultimate Booking Addon (wedesigntech-ultimate-booking-addon)
All plugin versions from initial release through 1.0.1
WordPress sites with the plugin installed and activated

Discovery Timeline

2026-03-05 - CVE-2026-27390 published to NVD
2026-04-22 - Last updated in NVD database

Technical Details for CVE-2026-27390

Vulnerability Analysis

The vulnerability is classified under [CWE-288]: Authentication Bypass Using an Alternate Path or Channel. The WeDesignTech Ultimate Booking Addon exposes a secondary code path that performs sensitive account operations without correctly validating the requestor's identity. Attackers with a low-privilege account, such as a subscriber or customer, can invoke this alternate path to act on behalf of other users, including administrators. The Patchstack advisory categorizes the resulting condition as an account takeover. Because the plugin handles booking workflows tied to user accounts, the affected logic likely involves account binding or session handling tied to booking endpoints.

Root Cause

The root cause is improper enforcement of authentication on a secondary execution path within the plugin. Primary endpoints in the plugin enforce identity checks, but an alternate channel reaches the same privileged functionality without verifying that the authenticated session belongs to the target account. This pattern commonly arises when AJAX handlers, REST routes, or form submission processors skip nonce validation, capability checks, or user-ID verification before mutating account state.

Attack Vector

Exploitation requires network access to the WordPress site and a low-privileged authenticated account on the target instance. The attacker sends a crafted request to the vulnerable plugin endpoint, supplying parameters that reference another user's account. The plugin processes the request through the alternate path and applies the requested modification, such as resetting credentials or rebinding the session. The attacker then logs in as the targeted user. No user interaction from the victim is required.

No public proof-of-concept code is available at this time. Refer to the Patchstack Vulnerability Report for additional technical context.

Detection Methods for CVE-2026-27390

Indicators of Compromise

Unexpected password changes or email address modifications on WordPress user accounts without corresponding administrative action.
New administrator accounts created shortly after low-privilege account activity in the WordPress audit log.
Authenticated POST or AJAX requests to wedesigntech-ultimate-booking-addon plugin endpoints referencing user IDs other than the requesting user.

Detection Strategies

Inspect web server access logs for repeated authenticated requests to plugin endpoints under /wp-admin/admin-ajax.php or plugin-specific REST routes that include user identifier parameters.
Correlate WordPress authentication events with subsequent administrative role assignments occurring from the same session or IP address.
Alert on session activity where a low-privilege user agent immediately precedes a successful administrator login from the same IP.

Monitoring Recommendations

Enable WordPress audit logging for user profile changes, password resets, and role modifications.
Forward WordPress and web server logs to a centralized SIEM for correlation against authentication anomalies.
Monitor for plugin file integrity changes and unexpected administrator account creation across managed WordPress fleets.

How to Mitigate CVE-2026-27390

Immediate Actions Required

Deactivate and remove the WeDesignTech Ultimate Booking Addon plugin until a patched version is available.
Audit all WordPress user accounts for unauthorized role changes, email address modifications, and unfamiliar administrator accounts.
Force a password reset for all users and invalidate active sessions on affected WordPress sites.
Restrict registration and limit low-privilege account creation while remediation is in progress.

Patch Information

At the time of publication, the Patchstack advisory lists affected versions through 1.0.1 with no fixed version specified. Monitor the Patchstack Vulnerability Report and the plugin vendor's release notes for an updated version that addresses the authentication bypass.

Workarounds

Block public access to plugin AJAX and REST endpoints at the web application firewall (WAF) layer until a vendor patch is released.
Disable new user registration in WordPress general settings to prevent attackers from obtaining the low-privilege foothold required for exploitation.
Enforce multi-factor authentication on all administrator accounts to limit the impact of credential compromise.

bash

# Configuration example: temporarily disable the vulnerable plugin via WP-CLI
wp plugin deactivate wedesigntech-ultimate-booking-addon
wp plugin delete wedesigntech-ultimate-booking-addon

# Disable open registration in wp-config.php hardening
wp option update users_can_register 0