CVE-2026-92421 Overview
CVE-2026-92421 is an Insecure Direct Object Reference (IDOR) vulnerability in the Hydra Booking — Appointment Scheduling & Booking Calendar WordPress plugin before version 1.2.3. The plugin fails to verify that a host record being modified belongs to the authenticated user submitting the request. An authenticated user assigned the plugin's host role can modify other hosts' profile data. The attacker can also reassign ownership of another host's record to their own account. The issue is classified under CWE-639: Authorization Bypass Through User-Controlled Key.
Critical Impact
Authenticated host-role users can tamper with other hosts' profile data and hijack ownership of appointment records within the same WordPress site.
Affected Products
- Hydra Booking — Appointment Scheduling & Booking Calendar WordPress plugin versions before 1.2.3
- WordPress sites exposing the plugin's host role to multiple users
- Multi-tenant booking deployments relying on the plugin for host isolation
Discovery Timeline
- 2026-09-19 - CVE-2026-92421 published to NVD
- 2026-09-21 - Last updated in NVD database
Technical Details for CVE-2026-92421
Vulnerability Analysis
The Hydra Booking plugin exposes endpoints that allow users with the host role to update their own host profile records. The update handler accepts a host record identifier from the request but does not validate that the identifier belongs to the user submitting the change. Any authenticated host can supply an arbitrary host ID and overwrite that record's fields.
The missing ownership check also extends to fields that determine record ownership. As a result, an attacker can reassign a target host's record so that the attacker becomes its owner. This grants the attacker downstream control over the appointments, availability windows, and profile data tied to the hijacked host.
The flaw requires authentication and a host-role assignment, limiting exploitation to insiders or attackers who first obtain host credentials. Impact is confined to the WordPress instance running the vulnerable plugin.
Root Cause
The root cause is a missing authorization check on the host record identifier passed into the update handler. The plugin trusts the client-supplied ID and performs the write without confirming the record's owner matches the current user. This pattern is characteristic of CWE-639.
Attack Vector
Exploitation occurs over the network against the WordPress admin or AJAX endpoints exposed by the plugin. An authenticated host-role user submits a modified request substituting another host's record identifier. The server processes the change without validation, applying the attacker-controlled data — including ownership fields — to the targeted record. No user interaction is required from the victim.
Refer to the WPScan Vulnerability Report for additional technical details.
Detection Methods for CVE-2026-92421
Indicators of Compromise
- Unexpected changes to host profile fields (name, email, availability) attributed to a different host account
- Host record ownership transfers logged in the WordPress database that do not match administrative actions
- Repeated POST requests to Hydra Booking host update endpoints from a single authenticated user targeting varying host IDs
Detection Strategies
- Review WordPress and plugin audit logs for host record updates where the acting user does not match the record's prior owner
- Correlate web server access logs with authenticated session identifiers to flag host update requests carrying non-owned record IDs
- Compare current host records against backups to identify silent modifications or ownership reassignments
Monitoring Recommendations
- Enable verbose logging on Hydra Booking administrative endpoints and forward events to a centralized SIEM
- Alert on any modification of the ownership column in the plugin's host table outside of expected administrative workflows
- Track sudden spikes in host profile update requests from single accounts to detect enumeration attempts
How to Mitigate CVE-2026-92421
Immediate Actions Required
- Upgrade the Hydra Booking plugin to version 1.2.3 or later on all WordPress installations
- Audit existing host records for unauthorized ownership changes and revert affected entries from backups
- Rotate credentials for any host-role accounts suspected of compromise or misuse
Patch Information
The vendor addressed the missing authorization check in Hydra Booking version 1.2.3. Update through the WordPress plugin dashboard or by deploying the fixed release from the official plugin repository. Details are available in the WPScan Vulnerability Report.
Workarounds
- Temporarily revoke the plugin's host role from untrusted users until the patch is applied
- Restrict access to the WordPress /wp-admin/ and AJAX endpoints via IP allowlisting where feasible
- Disable the Hydra Booking plugin on production sites that cannot be updated immediately
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
