CVE-2025-11517 is an authorization bypass vulnerability classified under CWE-639 (Authorization Bypass Through User-Controlled Key) affecting the Event Tickets and Registration plugin for WordPress. The vulnerability resides in the REST API endpoint /wp-json/tribe/tickets/v1/commerce/free/order, which is intended to handle free ticket orders. However, the endpoint does not verify whether the ticket type requested is actually free, allowing attackers to manipulate the request to obtain paid tickets without completing payment. This flaw enables unauthenticated attackers to exploit the system remotely without any user interaction or privileges. The vulnerability impacts all versions up to and including 5.26.5 of the plugin. The CVSS v3.1 base score is 7.5, reflecting high severity due to the ease of exploitation (network vector, no privileges required, no user interaction) and the significant impact on integrity (unauthorized acquisition of paid tickets). While confidentiality and availability are not affected, the integrity breach results in financial loss and potential reputational damage for organizations relying on this plugin for event ticketing. No patches or exploit code are currently publicly available, but the vulnerability has been officially published and assigned a CVE identifier. The plugin is widely used in WordPress-based event management systems, making this a relevant threat for many organizations globally, including those in Europe.

The primary impact of CVE-2025-11517 is financial, as attackers can bypass payment mechanisms to obtain paid tickets for free, directly causing revenue loss. This can also lead to reputational damage if customers or partners perceive the event organizer as having weak security controls. For European organizations, especially those hosting large-scale events or relying heavily on online ticket sales through WordPress, this vulnerability could disrupt business operations and erode trust. Additionally, unauthorized ticket acquisition could lead to overcapacity issues at events, logistical challenges, and potential safety risks. The lack of authentication and user interaction requirements increases the risk of widespread exploitation. While no known exploits are currently active, the vulnerability’s public disclosure means attackers could develop exploits rapidly. Organizations in Europe with significant event management activities, particularly in countries with high WordPress adoption, face elevated risks.

1. Monitor the Event Tickets and Registration plugin vendor announcements closely and apply security patches immediately once released. 2. Until a patch is available, restrict access to the vulnerable REST API endpoint by implementing web application firewall (WAF) rules that block or rate-limit requests to /wp-json/tribe/tickets/v1/commerce/free/order from unauthenticated users. 3. Employ strict access controls and authentication mechanisms around ticket purchasing workflows to detect and prevent unauthorized ticket acquisition. 4. Enable detailed logging and monitoring of ticket order activities to identify anomalous patterns indicative of exploitation attempts. 5. Consider temporarily disabling the plugin or the ticket purchasing feature if patching or mitigation is not feasible in the short term. 6. Educate event management and IT teams about the vulnerability and encourage vigilance for suspicious ticketing activity. 7. Review and harden overall WordPress security posture, including plugin management and REST API exposure, to reduce attack surface.