CVE-2025-30821: H5PxAPIkatchu Authorization Bypass Flaw

CVE-2025-30821 Overview

CVE-2025-30821 is a missing authorization vulnerability affecting the SNORDIAN's H5PxAPIkatchu WordPress plugin by otacke. The plugin exposes functionality that is not properly constrained by access control lists (ACLs), allowing unauthenticated users to reach actions that should require privilege checks. The issue is classified under CWE-862: Missing Authorization. All plugin versions up to and including 0.4.14 are affected.

Critical Impact
Unauthenticated attackers can access functionality not properly restricted by ACLs, potentially impacting plugin availability on WordPress sites running H5PxAPIkatchu <= 0.4.14.

Affected Products

SNORDIAN's H5PxAPIkatchu WordPress plugin (vendor: otacke)
All versions from initial release through 0.4.14
WordPress installations that have the plugin activated

Discovery Timeline

2025-03-27 - CVE-2025-30821 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-30821

Vulnerability Analysis

The H5PxAPIkatchu plugin captures xAPI statements generated by H5P content in WordPress. The vulnerability stems from broken access control on one or more plugin endpoints. Functionality intended for privileged users is reachable without proper authorization checks. Because the attack vector is network-based and requires no authentication or user interaction, remote actors can invoke the exposed functionality directly against affected WordPress sites.

The scope of impact is limited to availability. Confidentiality and integrity are not affected according to the published CVSS vector. Attackers cannot read protected data or modify records, but they can trigger plugin behavior that degrades service.

The Patchstack Vulnerability Report provides additional technical context for defenders and plugin maintainers.

Root Cause

The root cause is a missing capability check in the plugin's request handling logic. WordPress plugins must gate privileged actions with functions such as current_user_can() and validate nonces via check_admin_referer() or wp_verify_nonce(). In H5PxAPIkatchu <= 0.4.14, at least one handler executes without enforcing these controls, mapping to CWE-862.

Attack Vector

An attacker sends crafted HTTP requests to the exposed plugin endpoint on a target WordPress site. No credentials, session, or user interaction are required. The request invokes the unprotected functionality directly. Refer to the linked Patchstack advisory for endpoint-level detail; no verified proof-of-concept code is publicly available.

Detection Methods for CVE-2025-30821

Indicators of Compromise

Unexpected HTTP requests from unauthenticated sources to H5PxAPIkatchu plugin endpoints under /wp-content/plugins/h5pxapikatchu/ or plugin-specific admin-ajax.php actions
Anomalous spikes in xAPI-related database writes or plugin log entries originating from non-authenticated sessions
Plugin-triggered actions that occur outside expected administrator workflows

Detection Strategies

Review WordPress access logs for requests to plugin endpoints that return HTTP 200 without an authenticated session cookie
Compare the installed plugin version against 0.4.14 across all WordPress instances and flag vulnerable versions
Use a WordPress vulnerability scanner or the Patchstack database to identify sites running affected releases

Monitoring Recommendations

Enable web server and WordPress audit logging for all admin-ajax.php and REST API calls invoking H5PxAPIkatchu actions
Alert on high request rates to plugin endpoints from single source IPs
Track plugin database tables for anomalous write volumes that could indicate abuse of the unauthorized functionality

How to Mitigate CVE-2025-30821

Immediate Actions Required

Inventory all WordPress installations and identify sites running H5PxAPIkatchu <= 0.4.14
Deactivate the plugin on affected sites until a patched version is confirmed available from the maintainer
Restrict access to wp-admin and admin-ajax.php endpoints via IP allowlisting where operationally feasible

Patch Information

At the time of publication, no fixed version beyond 0.4.14 is referenced in the NVD entry. Monitor the Patchstack Vulnerability Report and the plugin's WordPress.org repository for a security release. Apply the update to all affected sites once available.

Workarounds

Uninstall or deactivate H5PxAPIkatchu on WordPress instances where H5P xAPI capture is not business-critical
Deploy a Web Application Firewall (WAF) rule blocking unauthenticated requests to plugin-specific endpoints
Enforce authentication at the reverse proxy or WAF layer for all admin-ajax.php actions associated with the plugin

bash

# Example WAF rule concept: block unauthenticated POSTs to plugin endpoints
# Adapt to your WAF syntax (ModSecurity, Cloudflare, AWS WAF, etc.)
SecRule REQUEST_URI "@contains /wp-content/plugins/h5pxapikatchu/" \
  "id:1030821,phase:1,deny,status:403,\
   chain,msg:'CVE-2025-30821 - block unauthenticated H5PxAPIkatchu access'"
  SecRule &REQUEST_COOKIES:/wordpress_logged_in_/ "@eq 0"