CVE-2025-4691
📋 TL;DR
The Free Booking Plugin for WordPress is vulnerable to Insecure Direct Object Reference (IDOR) allowing unauthenticated attackers to view any booking request details. This affects all versions up to 1.3.21. The vulnerability was partially patched in versions 1.3.18 and 1.3.21 but remains exploitable.
💻 Affected Systems
- Free Booking Plugin for Hotels, Restaurants and Car Rentals – eaSYNC Booking
📦 What is this software?
Easync by Syntacticsinc
⚠️ Risk & Real-World Impact
Worst Case
Attackers could access sensitive booking information including personal details, payment information, and reservation data for all customers, potentially leading to data breaches and privacy violations.
Likely Case
Unauthenticated attackers will access booking details they shouldn't have permission to view, exposing customer names, contact information, dates, and service details.
If Mitigated
With proper access controls and validation, only authorized users can view booking details, preventing unauthorized data exposure.
🎯 Exploit Status
The vulnerability requires no authentication and involves manipulating a user-controlled key parameter. Exploitation is straightforward for attackers with basic web testing knowledge.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 1.3.21
Vendor Advisory: https://plugins.trac.wordpress.org/changeset/3300408/
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins → Installed Plugins. 3. Find 'Free Booking Plugin for Hotels, Restaurants and Car Rentals – eaSYNC Booking'. 4. Click 'Update Now' if available. 5. If no update is available, deactivate and delete the plugin, then install the latest version from WordPress repository.
🔧 Temporary Workarounds
Disable vulnerable endpoint via .htaccess
linuxBlock access to the vulnerable function using Apache rewrite rules
RewriteEngine On
RewriteCond %{QUERY_STRING} view_request_details [NC]
RewriteRule ^ - [F]
Temporary plugin deactivation
allDisable the plugin until patched version is available
wp plugin deactivate easync-booking
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block requests containing 'view_request_details' parameter manipulation
- Restrict access to the WordPress admin area using IP whitelisting and strong authentication
🔍 How to Verify
Check if Vulnerable:
Check WordPress plugin version in admin panel or use: wp plugin list --name=easync-booking --field=versionCheck Version:
wp plugin list --name=easync-booking --field=versionVerify Fix Applied:
Verify plugin version is greater than 1.3.21 and test the vulnerable endpoint with unauthorized requests📡 Detection & Monitoring
Log Indicators:
- Multiple requests to booking endpoints with different ID parameters from same IP
- Unauthorized access attempts to view_request_details function
Network Indicators:
- HTTP requests with 'view_request_details' parameter and sequential/non-sequential ID values
SIEM Query:
source="web_logs" AND uri="*view_request_details*" AND status=200 AND user_agent NOT IN ("admin_user_agents")🔗 References
- https://plugins.trac.wordpress.org/browser/easync-booking/tags/1.3.17/easync.php#L4859
- https://plugins.trac.wordpress.org/changeset/3243634/
- https://plugins.trac.wordpress.org/changeset/3293607/
- https://plugins.trac.wordpress.org/changeset/3300408/
- https://www.wordfence.com/threat-intel/vulnerabilities/id/3c9953b3-dd09-4c80-be11-4daf3bbac720?source=cve
