CVE-2026-91008 Overview
CVE-2026-91008 is an Insecure Direct Object Reference (IDOR) [CWE-639] vulnerability in the Event Booking Manager for WooCommerce WordPress plugin before version 5.3.8. The plugin renders booking confirmation details without verifying ownership or authorization. Unauthenticated attackers can retrieve registered attendees' personal information by supplying an enumerable booking reference. Exposed data includes full name, email address, phone number, and custom registration fields. Exploitation is limited to sites configured to use the plugin's native (non-WooCommerce) checkout, which is not the default configuration.
Critical Impact
Unauthenticated disclosure of attendee personally identifiable information (PII) through enumerable booking references on sites using the plugin's native checkout flow.
Affected Products
- Event Booking Manager for WooCommerce WordPress plugin versions before 5.3.8
- WordPress sites configured with the plugin's native (non-WooCommerce) checkout
- Installations exposing booking confirmation endpoints to unauthenticated visitors
Discovery Timeline
- 2026-09-17 - CVE-2026-91008 published to NVD
- 2026-09-17 - Last updated in NVD database
Technical Details for CVE-2026-91008
Vulnerability Analysis
The vulnerability resides in the booking confirmation rendering logic of the Event Booking Manager for WooCommerce WordPress plugin. When a user completes a booking through the native checkout flow, the plugin generates a booking reference and renders a confirmation page keyed on that reference. The plugin fails to validate whether the requesting session owns the referenced booking. Any unauthenticated visitor supplying a valid reference receives the associated attendee record.
Because booking references are enumerable rather than cryptographically random, an attacker can iterate through the reference space and harvest attendee records at scale. The exposed fields include full names, email addresses, phone numbers, and any custom registration fields the site operator configured. The attack requires no authentication and no user interaction, though exploitation is limited to sites that opted out of the default WooCommerce checkout in favor of the plugin's native checkout path.
Root Cause
The root cause is a missing authorization check on the booking confirmation handler, mapped to [CWE-639] Authorization Bypass Through User-Controlled Key. The handler trusts the booking reference supplied in the request as sufficient proof of access rather than binding the reference to the authenticated user or a session-scoped token.
Attack Vector
The attack vector is network-based and requires no privileges or user interaction. An attacker enumerates booking references by iterating predictable identifiers against the confirmation endpoint. Each successful request returns a rendered confirmation page containing the attendee's PII. The attacker can automate collection using standard HTTP tooling.
No verified public exploit code is available. See the WPScan Vulnerability Report for additional technical detail.
Detection Methods for CVE-2026-91008
Indicators of Compromise
- High volumes of sequential or patterned requests against the booking confirmation endpoint from a single source address
- Unusual outbound responses containing attendee PII correlated with unauthenticated sessions
- Web server access logs showing repeated GET requests varying only the booking reference parameter
Detection Strategies
- Inspect web access logs for enumeration patterns targeting booking confirmation URLs on WordPress sites running the plugin
- Deploy web application firewall (WAF) rules that rate-limit and alert on repeated access to confirmation endpoints by unauthenticated clients
- Correlate anomalous response sizes and status codes on confirmation routes to surface bulk data retrieval attempts
Monitoring Recommendations
- Monitor plugin version inventory across WordPress deployments and flag any instance below version 5.3.8
- Track checkout configuration to identify sites using the plugin's native checkout, where the vulnerability is exploitable
- Alert on spikes in traffic to booking confirmation URLs from non-referrer or scripted user-agent sources
How to Mitigate CVE-2026-91008
Immediate Actions Required
- Upgrade the Event Booking Manager for WooCommerce WordPress plugin to version 5.3.8 or later
- Audit checkout configuration and revert to the WooCommerce checkout flow where feasible, since the native checkout is the exploitable configuration
- Review web server logs for prior enumeration attempts against booking confirmation endpoints and notify affected attendees if disclosure is confirmed
Patch Information
The vendor addressed CVE-2026-91008 in version 5.3.8 of the Event Booking Manager for WooCommerce WordPress plugin. The fix introduces an ownership or authorization check before rendering booking confirmation details. Refer to the WPScan Vulnerability Report for advisory details.
Workarounds
- Switch the plugin configuration to use the default WooCommerce checkout, which is not affected by this vulnerability
- Restrict access to booking confirmation endpoints behind authentication or a signed, single-use token issued at checkout completion
- Deploy WAF rate limiting on confirmation endpoints to slow enumeration until the patched version is applied
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
