CVE-2025-66057 identifies a DOM-based Cross-site Scripting (XSS) vulnerability in the Bold Page Builder plugin developed by BoldThemes, affecting all versions up to and including 5.5.2. The vulnerability stems from improper neutralization of user-supplied input during the dynamic generation of web pages, which allows malicious actors to inject and execute arbitrary JavaScript code within the context of the victim's browser session. This type of XSS is client-side, meaning the malicious payload is executed in the Document Object Model (DOM) rather than server-side, complicating detection and mitigation. The attack vector is remote with no privileges required (AV:N/PR:N), but user interaction is necessary (UI:R), such as clicking a crafted URL or interacting with a maliciously crafted page element. The vulnerability affects confidentiality by potentially exposing sensitive user data, integrity by enabling unauthorized actions or content manipulation, and availability by possibly causing denial-of-service conditions through script execution. The CVSS v3.1 base score is 6.3, reflecting a medium severity level. No patches or official fixes have been released at the time of publication, and no known exploits are reported in the wild. The vulnerability is particularly relevant for websites using the Bold Page Builder plugin, commonly employed in WordPress environments for building and customizing web pages. Given the widespread use of WordPress in Europe, this vulnerability poses a tangible risk to organizations relying on this plugin for their web presence.

European organizations using the Bold Page Builder plugin face risks including data theft, session hijacking, and website defacement due to this DOM-based XSS vulnerability. Attackers can exploit the flaw to execute arbitrary scripts in users' browsers, potentially compromising user credentials, cookies, or other sensitive information. This can lead to unauthorized access to internal systems or customer data, damaging reputation and violating data protection regulations such as GDPR. The vulnerability may also facilitate phishing attacks or malware distribution by injecting malicious content into trusted websites. For e-commerce, financial, and public sector entities, the impact could extend to loss of customer trust and regulatory penalties. The requirement for user interaction limits automated exploitation but does not eliminate risk, especially in environments with high user traffic or where social engineering can be leveraged. The absence of patches increases exposure time, emphasizing the need for proactive mitigation. Overall, the vulnerability threatens confidentiality, integrity, and availability of affected web assets, with potential cascading effects on business operations and compliance obligations.

1. Monitor official BoldThemes channels and security advisories for the release of patches addressing CVE-2025-66057 and apply updates promptly. 2. Implement strict input validation and output encoding on all user-supplied data within the web application to prevent injection of malicious scripts. 3. Deploy Content Security Policy (CSP) headers to restrict the execution of untrusted scripts and reduce the impact of potential XSS attacks. 4. Use Web Application Firewalls (WAFs) configured to detect and block common XSS attack patterns targeting the Bold Page Builder plugin. 5. Educate users and administrators about the risks of clicking on untrusted links and encourage cautious behavior to reduce successful exploitation via social engineering. 6. Conduct regular security assessments and penetration testing focused on client-side vulnerabilities, including DOM-based XSS. 7. Where feasible, consider temporary disabling or replacing the Bold Page Builder plugin with alternative solutions until a secure version is available. 8. Review and harden browser security settings and encourage the use of modern browsers with built-in XSS protections among users.