CVE-2025-5586 is a stored Cross-Site Scripting (XSS) vulnerability affecting the WordPress plugin 'Ajax Load More and Infinite Scroll' developed by tushargohel. This vulnerability exists in all versions up to and including 1.6.0 due to improper input sanitization and output escaping of the 'id' parameter. Specifically, authenticated users with Contributor-level access or higher can inject malicious JavaScript code into pages via this parameter. When other users visit the compromised pages, the injected scripts execute in their browsers, potentially leading to session hijacking, privilege escalation, or other malicious activities. The vulnerability is classified under CWE-79, which relates to improper neutralization of input during web page generation. The CVSS v3.1 base score is 6.4, indicating a medium severity level. The attack vector is network-based (remote), with low attack complexity and requiring privileges (Contributor or above), but no user interaction is needed for exploitation. The scope is changed, meaning the vulnerability affects components beyond the initially vulnerable plugin, potentially impacting the confidentiality and integrity of the affected WordPress sites. No known exploits are currently reported in the wild, and no official patches have been published yet.

For European organizations using WordPress sites with the Ajax Load More and Infinite Scroll plugin, this vulnerability poses a significant risk to website integrity and user trust. Exploitation could allow malicious insiders or compromised contributor accounts to inject persistent malicious scripts, leading to theft of user credentials, session tokens, or other sensitive information. This could result in unauthorized access to administrative functions or customer data breaches. Given the widespread use of WordPress across Europe for corporate, governmental, and e-commerce websites, the impact includes potential reputational damage, regulatory non-compliance (e.g., GDPR violations due to data leakage), and operational disruptions. The vulnerability's ability to affect multiple users visiting the compromised pages increases the attack surface. Although the attack requires authenticated access, many organizations have contributors or editors with such privileges, making insider threats or account compromise plausible attack vectors.

European organizations should immediately audit their WordPress installations for the presence of the Ajax Load More and Infinite Scroll plugin and verify the version in use. Until an official patch is released, organizations should consider disabling or removing the plugin to eliminate the attack vector. Implement strict role-based access controls to limit Contributor-level privileges only to trusted users and monitor for unusual contributor activity. Employ Web Application Firewalls (WAFs) with custom rules to detect and block suspicious payloads targeting the 'id' parameter. Additionally, enable Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts. Regularly review and sanitize user-generated content and conduct security awareness training for contributors to reduce the risk of malicious input. Once a patch becomes available, prioritize prompt application of updates. Finally, perform routine security scans and penetration tests focusing on XSS vulnerabilities to detect any residual or new issues.