CVE-2024-12273 is a stored Cross-Site Scripting (XSS) vulnerability identified in the Calculated Fields Form WordPress plugin versions prior to 5.2.62. This plugin allows users to create forms with dynamically calculated fields, commonly used for data collection and processing on WordPress sites. The vulnerability arises because certain plugin settings are not properly sanitized or escaped before being stored and rendered. This flaw enables high-privilege users, such as administrators, to inject malicious JavaScript code that is persistently stored and executed in the context of other users viewing the affected pages. Notably, this XSS can be exploited even when the WordPress capability 'unfiltered_html' is disabled, such as in multisite environments, which typically restricts HTML input to prevent such attacks. The vulnerability requires high privileges (admin-level access) and user interaction, as the malicious payload is triggered when a victim views the stored content. The CVSS 3.1 base score is 3.5 (low severity), reflecting limited confidentiality and integrity impacts, no availability impact, network attack vector, low attack complexity, and requirement for high privileges and user interaction. There are no known exploits in the wild at this time, and no official patches have been linked yet. The vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation), a common web application security issue. The plugin is widely used in WordPress environments for form creation, and the vulnerability could be leveraged to execute arbitrary scripts, potentially leading to session hijacking, privilege escalation, or defacement within the scope of the affected site and user roles.

For European organizations using the Calculated Fields Form plugin on WordPress sites, this vulnerability poses a moderate risk primarily to site integrity and user trust. Although exploitation requires administrator-level access, a compromised admin account or insider threat could inject malicious scripts that execute in the browsers of other users, potentially leading to session hijacking, theft of sensitive data, or unauthorized actions within the site. This could affect internal portals, customer-facing websites, or intranet applications relying on this plugin. The impact on confidentiality and integrity is limited to the scope of the WordPress site and its users, with no direct availability impact. However, reputational damage and compliance risks (e.g., GDPR) could arise if user data is exposed or manipulated. The risk is heightened in multisite WordPress deployments common in large European enterprises and public sector organizations, where the usual HTML filtering restrictions may not prevent exploitation. Given the low CVSS score but the potential for persistent XSS, organizations should not dismiss this vulnerability, especially those with high-value web assets or sensitive user bases.

To mitigate CVE-2024-12273 effectively, European organizations should take the following specific actions: 1) Immediately update the Calculated Fields Form plugin to version 5.2.62 or later once available, as this will include the necessary sanitization and escaping fixes. 2) Until a patch is applied, restrict administrative access to the WordPress backend strictly, enforcing strong authentication methods such as MFA and limiting admin accounts to trusted personnel only. 3) Review and audit all stored form settings and inputs created via the plugin for suspicious or unexpected scripts or HTML content, removing any potentially malicious entries. 4) Implement Content Security Policy (CSP) headers to limit the execution of unauthorized scripts on affected WordPress sites, reducing the impact of any injected code. 5) Monitor web server and application logs for unusual activity indicative of XSS exploitation attempts or privilege misuse. 6) In multisite environments, verify that user roles and capabilities are correctly assigned and consider additional filtering or input validation controls at the application or web application firewall (WAF) level. 7) Educate administrators about the risks of stored XSS and safe plugin configuration practices. These targeted measures go beyond generic patching advice and address the specific exploitation vectors and operational contexts of this vulnerability.