SNORDIAN's H5PxAPIkatchu WordPress Plugin Stored Cross-Site Scripting Vulnerability

A stored cross-site scripting vulnerability has been identified in the SNORDIAN's H5PxAPIkatchu plugin for WordPress, affecting all versions through 0.4.17. The vulnerability arises from inadequate input sanitization and output escaping in the 'insert_data' AJAX endpoint, allowing unauthenticated attackers to inject arbitrary web scripts. These scripts are executed when a user accesses the compromised page.

Impact

Exploitation of this vulnerability allows for stored cross-site scripting, where injected scripts are executed in the context of the user viewing the page.

Reproduction

To reproduce this vulnerability, an unauthenticated user can send a request to the 'insert_data' AJAX endpoint with a payload containing the desired script. The absence of proper nonce verification in the request allows the injection to be processed and stored. Once injected, the script will execute whenever the affected page is accessed.

Remediation

Users are advised to update the SNORDIAN's H5PxAPIkatchu WordPress plugin to version 0.4.18 or later.