CVE-2025-62943 is a stored Cross-site Scripting (XSS) vulnerability identified in the WordPress plugin 'Next Page, Not Next Post' developed by Matt McInvale. This plugin, which facilitates navigation between pages rather than posts, improperly neutralizes user input during the generation of web pages, allowing malicious scripts to be stored persistently within the site content. When a victim accesses the affected page, the malicious script executes in their browser context, potentially leading to session hijacking, theft of cookies, redirection to malicious sites, or defacement. The vulnerability affects all versions up to and including 0.3.0, with no patch currently available or linked. Exploitation does not require authentication or user interaction beyond visiting the compromised page, increasing the attack surface. Although no known exploits have been reported in the wild, the vulnerability's presence in a popular content management system plugin makes it a notable risk. The lack of a CVSS score necessitates an assessment based on the impact on confidentiality, integrity, and availability, ease of exploitation, and scope of affected systems. Stored XSS vulnerabilities are particularly dangerous because they can affect all users visiting the compromised site and can be leveraged for further attacks such as privilege escalation or malware delivery.

For European organizations, especially those operating WordPress-based websites using the 'Next Page, Not Next Post' plugin, this vulnerability could lead to significant security incidents. Attackers could inject persistent malicious scripts that compromise user sessions, steal sensitive information, or manipulate website content, damaging organizational reputation and trust. The impact extends to customers and partners interacting with the affected websites, potentially exposing them to phishing or malware. Given the plugin's role in navigation, the vulnerability could be exploited on high-traffic pages, amplifying the reach of attacks. Additionally, regulatory frameworks such as GDPR impose strict data protection requirements; a breach resulting from this vulnerability could lead to legal and financial penalties. The absence of a patch increases the urgency for interim protective measures. Organizations with public-facing WordPress sites are particularly vulnerable, and the risk is heightened in sectors with high web presence such as media, e-commerce, and public services.

1. Monitor the vendor’s official channels and security advisories for an official patch and apply it immediately upon release. 2. Until a patch is available, implement manual input validation and output encoding to neutralize potentially malicious input within the plugin’s codebase, focusing on areas where user input is rendered. 3. Employ Web Application Firewalls (WAFs) with rules designed to detect and block common XSS attack patterns targeting the plugin’s endpoints. 4. Conduct regular security audits and penetration testing on WordPress sites to identify and remediate XSS and other injection vulnerabilities. 5. Educate site administrators and content creators about the risks of injecting untrusted content and enforce strict content policies. 6. Limit plugin usage to trusted administrators and consider disabling or uninstalling the plugin if it is not essential. 7. Implement Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts on the website. 8. Maintain regular backups of website data to enable quick recovery in case of compromise.