CVE-2025-5144 is a stored Cross-Site Scripting (XSS) vulnerability identified in The Events Calendar plugin for WordPress, affecting all versions up to and including 6.13.2. The root cause is insufficient sanitization and escaping of user-supplied input in the ‘data-date-*’ parameters, which are used during web page generation. This flaw allows authenticated attackers with at least Contributor-level privileges to inject arbitrary JavaScript code into calendar pages. When other users access these pages, the malicious scripts execute in their browsers, potentially leading to session hijacking, privilege escalation, or data theft. The vulnerability has a CVSS 3.1 base score of 6.4, reflecting medium severity, with network attack vector, low attack complexity, and requiring privileges but no user interaction. The scope is changed, indicating that the vulnerability affects resources beyond the attacker’s privileges, impacting confidentiality and integrity but not availability. No public exploits are currently known, but the vulnerability’s presence in a widely used WordPress plugin makes it a significant concern for website administrators. The plugin’s popularity and the common use of Contributor-level accounts for content management increase the risk of exploitation. The vulnerability highlights the importance of proper input validation and output encoding in web applications, especially in plugins that handle dynamic content generation.

The primary impact of CVE-2025-5144 is the potential compromise of user confidentiality and integrity on websites using The Events Calendar plugin. Successful exploitation can lead to session hijacking, unauthorized actions performed on behalf of users, and theft of sensitive information such as authentication tokens or personal data. Since the vulnerability is stored XSS, malicious scripts persist and affect multiple users, increasing the attack surface. Organizations relying on this plugin for event management on WordPress sites face risks of reputational damage, data breaches, and unauthorized access. Although availability is not directly impacted, the indirect effects of compromised user accounts or administrative privileges could lead to further exploitation or site defacement. The requirement for authenticated access limits the attack vector to insiders or registered users, but Contributor-level permissions are common, making exploitation feasible in many environments. The vulnerability could be leveraged in targeted attacks against organizations with high-value web assets or large user bases, potentially affecting sectors such as media, education, government, and e-commerce.

To mitigate CVE-2025-5144, organizations should immediately update The Events Calendar plugin to a version that addresses this vulnerability once available. In the absence of an official patch, administrators should restrict Contributor-level and higher permissions to trusted users only and review existing user roles to minimize unnecessary privileges. Implementing Web Application Firewalls (WAFs) with custom rules to detect and block suspicious ‘data-date-*’ parameter inputs can provide interim protection. Additionally, applying Content Security Policy (CSP) headers can limit the impact of injected scripts by restricting script execution sources. Regularly auditing plugin configurations and monitoring web logs for unusual activity related to calendar pages is recommended. Educating content contributors about the risks of injecting untrusted data and enforcing strict input validation on user-generated content can further reduce exploitation chances. Finally, consider isolating or sandboxing the plugin’s output if feasible to contain potential script execution.