CVE-2025-2524 is a Stored Cross-Site Scripting (XSS) vulnerability classified under CWE-79 affecting the Ninja Forms WordPress plugin prior to version 3.10.1. The root cause is the plugin's failure to properly sanitize and escape certain configuration settings, which allows high privilege users, typically administrators, to inject malicious JavaScript code into the plugin's stored data. This vulnerability is notable because it bypasses the usual WordPress security control of the unfiltered_html capability, meaning that even in environments where this capability is disabled (such as multisite WordPress installations), the vulnerability remains exploitable. The attack vector requires the attacker to have high privileges (admin level) and involves user interaction, such as an admin saving a malicious payload in the plugin settings. Upon execution, the malicious script could execute in the context of other administrators or users with elevated privileges, potentially leading to session hijacking, privilege escalation, or data manipulation. The CVSS v3.1 score is 4.8 (medium severity), reflecting the network attack vector, low complexity, high privileges required, and user interaction needed. The vulnerability impacts confidentiality and integrity but does not affect availability. No public exploits are currently known, and no official patches or mitigation links were provided at the time of publication. The vulnerability was reserved on March 19, 2025, and published on May 19, 2025, with enrichment from CISA and WPScan.

For European organizations, the impact of CVE-2025-2524 depends largely on the extent of Ninja Forms usage and the security posture regarding WordPress administration. Exploitation could allow attackers with admin privileges to inject malicious scripts that execute in the browsers of other administrators or privileged users, potentially leading to session hijacking, theft of sensitive information, or unauthorized actions within the WordPress environment. This could compromise the integrity of website content and administrative control, leading to reputational damage, data breaches, or further lateral movement within the organization’s infrastructure. Although availability is not directly impacted, the indirect consequences of compromised administrative accounts could result in downtime or defacement. European organizations operating WordPress multisite environments are particularly at risk due to the bypass of unfiltered_html restrictions. Given the medium severity and the requirement for high privileges, the threat is more relevant in environments with multiple administrators or where privilege escalation is possible. The lack of known exploits reduces immediate risk but does not eliminate the need for proactive mitigation.

1. Upgrade Ninja Forms to version 3.10.1 or later as soon as the patch becomes available to address the vulnerability directly. 2. Restrict administrative privileges strictly to trusted personnel and regularly audit user roles to minimize the number of high privilege users. 3. Implement a robust WordPress security policy including the use of security plugins that monitor and block suspicious admin activities or script injections. 4. Employ Content Security Policy (CSP) headers to limit the execution of unauthorized scripts within the WordPress admin interface. 5. Regularly review and sanitize all plugin settings and inputs, especially those editable by administrators, to detect and remove any injected scripts. 6. Use multi-factor authentication (MFA) for all administrative accounts to reduce the risk of credential compromise. 7. Monitor logs for unusual admin activity or changes in plugin settings that could indicate exploitation attempts. 8. For multisite WordPress setups, ensure that site administrators have limited capabilities and consider additional isolation between sites to reduce cross-site impact. 9. Educate administrators about the risks of XSS and the importance of cautious handling of plugin configurations. 10. Maintain regular backups of WordPress sites to enable rapid recovery if compromise occurs.