CVE-2025-9499 is a stored Cross-Site Scripting (XSS) vulnerability found in the Ocean Extra plugin for WordPress, specifically affecting all versions up to and including 2.4.9. The vulnerability arises from improper neutralization of input during web page generation, classified under CWE-79. The root cause is insufficient input sanitization and output escaping on user-supplied attributes within the oceanwp_library shortcode. This flaw allows authenticated users 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, defacement, or redirection to malicious sites. The vulnerability has a CVSS 3.1 base score of 6.4, indicating a medium severity level. The attack vector is network-based with low attack complexity, requiring privileges equivalent to contributor-level access but no user interaction is needed for exploitation. The scope is changed, meaning the vulnerability can affect resources beyond the initially compromised component, impacting confidentiality and integrity but not availability. No known exploits are currently reported in the wild, and no official patches have been linked yet. This vulnerability is significant because WordPress powers a large portion of websites globally, and Ocean Extra is a popular plugin enhancing OceanWP themes, widely used for business and personal websites. Stored XSS vulnerabilities are particularly dangerous as they persist on the server and affect all visitors to the infected page, increasing the attack surface and potential damage.

For European organizations, this vulnerability poses a moderate risk, especially for those relying on WordPress sites using the Ocean Extra plugin. Exploitation could lead to unauthorized script execution, enabling attackers to steal session cookies, perform actions on behalf of users, or deliver further malware payloads. This can compromise user data confidentiality and integrity, damage organizational reputation, and lead to regulatory non-compliance under GDPR if personal data is exposed or manipulated. The risk is heightened for organizations with contributor-level users who might be targeted or compromised to inject malicious code. Since the vulnerability does not affect availability, denial-of-service is less of a concern, but the persistent nature of stored XSS can facilitate prolonged attacks and lateral movement within web applications. European businesses in sectors such as e-commerce, finance, healthcare, and government, which often use WordPress for public-facing sites, could face targeted exploitation attempts. The medium severity score suggests that while the vulnerability is not critical, it requires timely remediation to prevent exploitation.

1. Immediate mitigation involves restricting contributor-level access to trusted users only and auditing existing contributor accounts for suspicious activity. 2. Disable or remove the Ocean Extra plugin if it is not essential to reduce the attack surface. 3. Implement Web Application Firewall (WAF) rules specifically targeting XSS payloads in shortcode attributes to block malicious input. 4. Monitor website logs for unusual shortcode usage or unexpected script injections. 5. Apply strict Content Security Policy (CSP) headers to limit the execution of unauthorized scripts on affected pages. 6. Regularly update the Ocean Extra plugin once the vendor releases a security patch addressing this vulnerability. 7. Educate content contributors about safe input practices and the risks of injecting untrusted content. 8. Conduct periodic security assessments and penetration testing focusing on WordPress plugins and user privilege management. These steps go beyond generic advice by focusing on access control, monitoring, and layered defenses tailored to this specific plugin vulnerability.