CVE-2025-58852 is a high-severity vulnerability identified in the Mark O'Donnell MSTW League Manager plugin, specifically affecting versions up to 2.10. The vulnerability is classified as a Cross-Site Request Forgery (CSRF) issue (CWE-352) that enables an attacker to perform unauthorized actions on behalf of an authenticated user. The exploitation of this CSRF vulnerability can lead to Stored Cross-Site Scripting (XSS), where malicious scripts are permanently stored within the application and executed in the context of users' browsers. This combination of CSRF and Stored XSS significantly increases the attack surface, allowing attackers to bypass normal authentication and authorization mechanisms by tricking users into submitting crafted requests. The CVSS 3.1 base score is 7.1, indicating a high severity level, with the vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L. This means the attack can be launched remotely over the network without privileges, requires user interaction, and affects confidentiality, integrity, and availability to a limited extent but with a scope change, implying that the vulnerability can impact resources beyond the initially vulnerable component. The vulnerability has been published recently (September 2025), and no known exploits are reported in the wild yet. No patches or fixes have been linked or released at the time of this report, which increases the urgency for mitigation. MSTW League Manager is a WordPress plugin used for managing sports leagues and teams, often deployed by sports clubs, schools, and community organizations to organize schedules, results, and player information. The presence of Stored XSS via CSRF can allow attackers to inject malicious scripts that execute in the browsers of site administrators or users, potentially leading to session hijacking, defacement, or further compromise of the hosting environment.

For European organizations, especially those involved in sports management, education, and community services that utilize the MSTW League Manager plugin, this vulnerability poses a significant risk. The Stored XSS enabled by CSRF can lead to unauthorized actions such as changing league data, injecting malicious content, or stealing sensitive user information including authentication tokens. This can result in reputational damage, data breaches, and disruption of services. Since the vulnerability affects confidentiality, integrity, and availability, organizations may face compliance issues under GDPR if personal data is compromised. The scope change in the CVSS vector suggests that the impact can extend beyond the plugin itself, potentially affecting other parts of the WordPress site or connected systems. The lack of a patch increases the window of exposure, and the requirement for user interaction means that targeted phishing or social engineering campaigns could be used to exploit this vulnerability. Given the widespread use of WordPress in Europe and the popularity of sports and community websites, the threat could affect a broad range of organizations, from small clubs to larger federations.

1. Immediate mitigation should include disabling or removing the MSTW League Manager plugin until a patch is available. 2. Implement Web Application Firewall (WAF) rules to detect and block CSRF and XSS attack patterns targeting the plugin endpoints. 3. Enforce strict Content Security Policy (CSP) headers to limit the execution of unauthorized scripts. 4. Educate users and administrators about the risks of clicking on suspicious links or performing actions from untrusted sources to reduce the risk of CSRF exploitation. 5. Monitor web server and application logs for unusual POST requests or suspicious activity related to the plugin. 6. Regularly update WordPress core and other plugins to minimize the attack surface. 7. Once a patch is released, prioritize testing and deploying it promptly. 8. Consider implementing multi-factor authentication (MFA) for administrative accounts to reduce the impact of session hijacking. 9. Conduct security audits and penetration testing focused on CSRF and XSS vulnerabilities in the web application environment.