Overview of CVE-2026-6810
A missing authorization vulnerability affects the Booking Calendar Contact Form plugin. This flaw has a CVSS score of 5.3. It is a medium-severity issue that needs attention. The vulnerability allows unauthorized access to certain plugin functions.
The plugin fails to check user permissions properly. This means any user can trigger protected actions. An attacker does not need authentication to exploit this flaw. They can access features meant for administrators only.
Technical Details
The vulnerability exists in the plugin’s REST API endpoints. These endpoints handle booking calendar data and contact form submissions. The plugin does not validate nonce tokens or capability checks. This makes it easy for attackers to exploit.
An unauthenticated user can send crafted HTTP requests. These requests modify or extract data from the plugin. The plugin processes these requests without verifying identity. This creates a serious data exposure risk.
The CVSS vector is AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N. This means the attack is network-based with low complexity. It requires no privileges and no user interaction. The impact is limited to confidentiality only.
Impact on Your Site
Attackers can view booking details and contact form entries. They can see customer names, email addresses, and phone numbers. This data leak can harm your business reputation. It also violates data protection regulations like GDPR.
The vulnerability does not allow data modification or deletion. However, reading sensitive information is dangerous enough. Your customers trust you with their personal data. A breach of that trust has lasting consequences.
How to Fix It
Update the Booking Calendar Contact Form plugin immediately. The vendor has released a patched version. Check your WordPress dashboard for updates. Apply the update as soon as possible.
If no update is available yet, disable the plugin temporarily. You can also add a web application firewall rule. This blocks unauthenticated requests to the plugin’s endpoints. Use a WordPress security plugin for extra protection.
Always keep your plugins updated. This is the best defense against known vulnerabilities. Monitor your site for unusual activity. Use a security scanner to check for missing authorization issues.
Conclusion
CVE-2026-6810 is a serious missing authorization flaw. It affects websites using Booking Calendar Contact Form. The CVSS score of 5.3 indicates moderate risk. But the ease of exploitation makes it critical to patch.
Update your plugin now to protect your data. Do not wait for an attacker to find your site first. Security is an ongoing process, not a one-time task. Stay vigilant and keep everything updated.
What Is Booking Calendar Contact Form?
Booking Calendar Contact Form is a WordPress plugin that adds appointment booking and contact form functionality to any site. It replaces both a booking system and a form builder in one package. Small businesses and service providers use it to accept reservations directly from their website.
The plugin stores booking data, customer details, and contact form submissions in the WordPress database. A missing authorization flaw puts all this data at risk.
Understanding CVE-2026-6810
CVE-2026-6810 is a missing authorization vulnerability. The plugin’s AJAX handlers do not check user capabilities before processing requests. Any authenticated user, including subscribers with minimal access, can access and modify booking data.
An attacker with a subscriber account can read other users’ booking information, including names, email addresses, phone numbers, and appointment details. They can also delete or modify existing bookings, causing data loss and confusion for your customers.
Impact on Your Business
This vulnerability exposes customer PII (personally identifiable information). If exploited, it could lead to GDPR or CCPA compliance violations. In some regions, data breach notification laws require you to inform affected customers within 72 hours.
Beyond legal risks, a compromised booking system damages your reputation. Customers who learn their data was exposed may take their business elsewhere.
Affected Versions and Fix
All versions below 1.0.17 are vulnerable. The developer patched the issue in version 1.0.17 by adding capability checks to all AJAX endpoints.
To update, go to Dashboard > Plugins and click Update Now on Booking Calendar Contact Form. After updating, verify that only administrators can access booking data by logging in as a subscriber and trying to reach the booking pages.
The Booking Calendar Contact Form plugin is available on wordpress.org/plugins/booking-calendar-contact-form/.