CVE-2025-5116 is a stored Cross-Site Scripting (XSS) vulnerability affecting the WP Plugin Info Card plugin for WordPress, specifically in all versions up to and including 5.3.1. The vulnerability arises from improper neutralization of input during web page generation, specifically through the 'containerid' parameter. This parameter lacks sufficient input sanitization and output escaping, allowing an authenticated attacker with Contributor-level access or higher to inject arbitrary malicious scripts into pages. These scripts execute whenever any user accesses the compromised page, potentially leading to session hijacking, privilege escalation, or other malicious activities. The vulnerability is a result of an incomplete patch for a previous related vulnerability (CVE-2025-31835), indicating that the underlying input validation issues were not fully resolved. The CVSS v3.1 base score is 6.4 (medium severity), with an attack vector of network, low attack complexity, requiring privileges (Contributor or above), no user interaction, and a scope change. The impact affects confidentiality and integrity but not availability. No known exploits are currently reported in the wild. The vulnerability is categorized under CWE-79, which is a common and critical web application security flaw related to improper input validation and output encoding in web applications.

For European organizations using WordPress with the WP Plugin Info Card plugin, this vulnerability poses a significant risk, especially for websites that allow multiple contributors or editors. An attacker with Contributor-level access could inject malicious scripts that execute in the browsers of site visitors or administrators, potentially leading to theft of authentication cookies, defacement, or unauthorized actions performed on behalf of users. This could compromise sensitive data, damage organizational reputation, and lead to regulatory compliance issues under GDPR if personal data is exposed or manipulated. Since WordPress is widely used across Europe for corporate, governmental, and non-profit websites, the risk is amplified in sectors with collaborative content management workflows. The vulnerability's exploitation could also facilitate further attacks within the network if administrative sessions are hijacked. However, the requirement for authenticated access limits the attack surface to insiders or compromised accounts, somewhat reducing the risk from external anonymous attackers.

European organizations should immediately verify if they use the WP Plugin Info Card plugin and identify the installed version. Since no official patch links are provided yet, organizations should consider the following mitigations: 1) Restrict Contributor-level access strictly to trusted users and review user permissions regularly to minimize the risk of malicious insiders. 2) Implement Web Application Firewall (WAF) rules to detect and block suspicious payloads targeting the 'containerid' parameter, focusing on script tags or typical XSS vectors. 3) Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts on affected sites. 4) Monitor logs and user activity for unusual behavior indicative of exploitation attempts. 5) Once an official patch is released, prioritize prompt testing and deployment. 6) Educate content contributors about safe input practices and the risks of injecting untrusted content. 7) Consider temporarily disabling or replacing the plugin if feasible until a secure version is available.