CVE-2026-42675: Hydra Booking Auth Bypass Vulnerability

CVE-2026-42675 Overview

CVE-2026-42675 is a Missing Authorization vulnerability [CWE-862] in the Themefic Hydra Booking plugin for WordPress. The flaw affects all versions of Hydra Booking up to and including 1.1.41. Attackers exploit incorrectly configured access control security levels to reach functionality that should require elevated privileges. The vulnerability is network-exploitable, requires no authentication, and needs no user interaction, making it accessible to unauthenticated remote actors. Successful exploitation impacts confidentiality, integrity, and availability of affected WordPress sites. The issue was published to the National Vulnerability Database (NVD) on June 1, 2026.

Critical Impact
Unauthenticated remote attackers can bypass authorization checks in Hydra Booking through version 1.1.41, gaining access to functionality that should be restricted by role-based access control.

Affected Products

Themefic Hydra Booking WordPress plugin
All versions from n/a through 1.1.41
WordPress sites with Hydra Booking installed and active

Discovery Timeline

2026-06-01 - CVE-2026-42675 published to NVD
2026-06-01 - Last updated in NVD database

Technical Details for CVE-2026-42675

Vulnerability Analysis

The vulnerability stems from missing authorization checks in the Hydra Booking plugin's request-handling logic. The plugin exposes functionality that performs sensitive operations without first validating that the calling user possesses the required capability or role. This pattern, classified under [CWE-862] Missing Authorization, allows requests to reach privileged code paths regardless of the requester's identity.

Because the attack vector is the network and no privileges or user interaction are required, an unauthenticated remote attacker can issue HTTP requests directly to the vulnerable endpoints. The vulnerability produces partial impacts across confidentiality, integrity, and availability, consistent with broken access control over booking-related data and administrative actions.

The Patchstack advisory describes the issue as broken access control resulting from incorrectly configured access control security levels in the plugin's exposed actions or REST routes.

Root Cause

The root cause is the absence of capability checks such as current_user_can() and missing nonce verification on plugin endpoints. WordPress plugins must explicitly enforce authorization on every AJAX handler, REST route, and admin-post action. Hydra Booking through version 1.1.41 registers handlers that execute without verifying the caller has the necessary role or capability for the operation.

Attack Vector

An attacker sends crafted HTTP requests to the vulnerable plugin endpoints exposed on a WordPress site running Hydra Booking ≤ 1.1.41. Because no authentication is required, the requests originate from any unauthenticated client on the network. The handler executes the requested action without confirming the caller's privilege level, granting access to booking data or administrative actions that should be restricted.

No verified public proof-of-concept code is available at the time of publication. Refer to the Patchstack Vulnerability Report for technical details.

Detection Methods for CVE-2026-42675

Indicators of Compromise

Unexpected HTTP POST or GET requests to Hydra Booking AJAX endpoints under /wp-admin/admin-ajax.php with plugin-specific action parameters from unauthenticated sources.
Requests to Hydra Booking REST routes under /wp-json/ originating from IP addresses that have never authenticated to the site.
Unexplained modifications, creations, or deletions of booking records, meeting types, or host configurations in the plugin's database tables.

Detection Strategies

Audit web server access logs for high-frequency requests to Hydra Booking endpoints lacking valid session cookies or X-WP-Nonce headers.
Compare booking-related database tables against backups to detect unauthorized changes consistent with broken access control exploitation.
Deploy Web Application Firewall (WAF) rules that alert on access to plugin endpoints without an authenticated WordPress session.

Monitoring Recommendations

Enable WordPress activity logging to capture all plugin actions, including the originating user ID and IP address for each request.
Monitor for installations of Hydra Booking versions ≤ 1.1.41 across the WordPress estate and flag them for remediation.
Alert on HTTP responses from plugin endpoints that return booking data or success codes to unauthenticated clients.

How to Mitigate CVE-2026-42675

Immediate Actions Required

Identify all WordPress sites running Themefic Hydra Booking and confirm the installed version.
Update Hydra Booking to a version newer than 1.1.41 once the vendor releases a patched release.
Restrict access to /wp-admin/admin-ajax.php and /wp-json/ plugin routes at the WAF layer until patching completes.
Review booking records and administrative settings for unauthorized changes during the exposure window.

Patch Information

The vulnerability affects Hydra Booking from an unspecified initial version through 1.1.41. Consult the Patchstack Vulnerability Report and the Themefic vendor channels for the fixed release version and upgrade instructions.

Workarounds

Deactivate and remove the Hydra Booking plugin until a patched version is installed.
Apply WAF rules that block unauthenticated requests to plugin-specific AJAX action parameters and REST namespaces.
Restrict access to the WordPress site by IP allowlist where booking functionality is not required for public users.

bash

# Example WAF rule logic blocking unauthenticated access to Hydra Booking endpoints
# (adapt to your WAF syntax — ModSecurity, Cloudflare, AWS WAF, etc.)
SecRule REQUEST_URI "@rx /wp-json/hydra-booking/" \
  "id:1042675,phase:1,deny,status:403,\
   chain,msg:'Block unauthenticated Hydra Booking access (CVE-2026-42675)'"
  SecRule &REQUEST_COOKIES:/wordpress_logged_in_/ "@eq 0"