CVE-2025-9852 identifies a stored Cross-Site Scripting (XSS) vulnerability in the Yoga Schedule Momoyoga plugin for WordPress, specifically in the 'momoyoga-schedule' shortcode. This vulnerability arises from insufficient sanitization and escaping of user-supplied attributes, allowing authenticated users with contributor-level permissions or higher to inject arbitrary JavaScript code into pages. When other users access these pages, the injected scripts execute in their browsers, potentially compromising session tokens, redirecting users, or performing unauthorized actions within the context of the affected site. The vulnerability affects all plugin versions up to and including 2.9.0. The CVSS 3.1 base score is 6.4, reflecting a medium severity with network attack vector, low attack complexity, and requiring privileges but no user interaction. The scope is changed, indicating that the vulnerability can affect resources beyond the initially vulnerable component. No public exploits are currently known, but the vulnerability poses a risk especially in multi-user WordPress environments where contributors can add or edit content. The lack of patches at the time of reporting means that organizations must rely on compensating controls until updates are released.

For European organizations, this vulnerability can lead to unauthorized script execution within their WordPress sites, potentially resulting in session hijacking, data theft, defacement, or distribution of malware to site visitors. Organizations in sectors such as wellness, fitness, and lifestyle that use the Yoga Schedule Momoyoga plugin are particularly at risk. The requirement for contributor-level access limits exploitation to insiders or compromised accounts, but insider threats or credential theft could enable attackers to exploit this vulnerability. The cross-site scripting can undermine user trust and damage brand reputation, especially in privacy-conscious European markets with strict data protection regulations like GDPR. Additionally, compromised sites could be used as vectors for further attacks or phishing campaigns targeting European users.

1. Immediately audit and restrict contributor-level access to trusted users only, minimizing the risk of malicious script injection. 2. Monitor and review all content created or edited via the 'momoyoga-schedule' shortcode for suspicious or unexpected code. 3. Employ Web Application Firewalls (WAFs) with rules to detect and block XSS payloads targeting this plugin’s shortcode parameters. 4. Disable or remove the Yoga Schedule Momoyoga plugin if it is not essential, or replace it with a more secure alternative. 5. Keep WordPress core and all plugins updated; apply security patches from the vendor promptly once available. 6. Implement Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts on affected sites. 7. Educate content contributors about secure content practices and the risks of injecting untrusted code. 8. Regularly scan websites for XSS vulnerabilities using automated tools and manual testing focused on shortcode inputs.