CVE-2025-30952 is a Stored Cross-Site Scripting (XSS) vulnerability classified under CWE-79, affecting the wpdive Nexa Blocks plugin for WordPress. This vulnerability arises from improper neutralization of input during web page generation, allowing malicious actors to inject and store arbitrary JavaScript code within the plugin's data handling processes. When a victim accesses a page containing the malicious payload, the injected script executes in their browser context, potentially leading to session hijacking, credential theft, or unauthorized actions performed on behalf of the user. The vulnerability affects Nexa Blocks versions up to and including 1.1.0, with no earlier version specified. The CVSS v3.1 base score is 6.5 (medium severity), indicating a moderate level of risk. The vector string (AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L) shows that the attack can be launched remotely over the network with low attack complexity, requires low privileges and user interaction, and impacts confidentiality, integrity, and availability to a limited extent. The scope is changed, meaning the vulnerability affects resources beyond the initially vulnerable component. No known exploits are currently reported in the wild, and no patches or fixes have been linked yet. Stored XSS vulnerabilities are particularly dangerous in WordPress plugins because they can affect site administrators and visitors alike, potentially compromising the entire site and its users. Given that Nexa Blocks is a WordPress plugin, the vulnerability is exploitable in environments where this plugin is installed and active, especially on sites that allow user-generated content or input that is not properly sanitized.

For European organizations, the impact of this vulnerability can be significant, especially for those relying on WordPress sites with the Nexa Blocks plugin installed. Exploitation could lead to unauthorized access to sensitive information, session hijacking of administrative accounts, defacement of websites, or distribution of malware to site visitors. This can damage organizational reputation, lead to data breaches involving personal data protected under GDPR, and cause operational disruptions. Since the vulnerability requires low privileges but user interaction, phishing or social engineering could be used to trick users into triggering the malicious payload. Organizations in sectors such as e-commerce, government, education, and media—where WordPress is widely used—may face increased risks. The potential for cross-site scripting to pivot into further attacks, such as privilege escalation or lateral movement within the network, also raises concerns about broader compromise. Additionally, the changed scope indicates that the impact could extend beyond the plugin itself, affecting other components or users within the web application environment.

To mitigate this vulnerability, European organizations should first identify all WordPress installations using the Nexa Blocks plugin and verify the version in use. Until an official patch is released, administrators should consider disabling or uninstalling the plugin to eliminate the attack surface. Implementing Web Application Firewalls (WAFs) with custom rules to detect and block typical XSS payloads targeting Nexa Blocks can provide temporary protection. Organizations should also enforce strict Content Security Policies (CSP) to restrict the execution of unauthorized scripts in browsers. Regularly auditing and sanitizing all user inputs and stored content on affected sites is critical to prevent injection of malicious scripts. Monitoring web server and application logs for unusual activity or repeated failed attempts to inject scripts can help detect exploitation attempts early. Educating users and administrators about the risks of clicking on suspicious links or interacting with untrusted content can reduce the likelihood of successful exploitation requiring user interaction. Finally, organizations should stay alert for official patches or updates from the vendor and apply them promptly once available.