CVE-2025-8420 is a high-severity remote code execution (RCE) vulnerability affecting the 'Request a Quote Form' plugin for WordPress developed by emarket-design, specifically versions up to and including 2.5.2. The vulnerability arises from improper input validation in the emd_form_builder_lite_pagenum function, where user-supplied input is used directly as a function name without adequate sanitization or neutralization. This constitutes an 'Eval Injection' (CWE-95) flaw, allowing unauthenticated attackers to invoke arbitrary functions on the server. Although the exploit does not permit passing parameters to these functions, the ability to call arbitrary functions can still lead to significant compromise, including executing malicious code, altering server behavior, or escalating privileges. The vulnerability is exploitable over the network without authentication or user interaction, but the attack complexity is rated high, likely due to the constraints on parameter passing and the need to identify callable functions that yield malicious outcomes. The CVSS v3.1 base score is 8.1, reflecting high impact on confidentiality, integrity, and availability. No known exploits are currently reported in the wild, and no official patches have been linked yet. The plugin is used for price quote request management in WordPress sites, which may be common in e-commerce and business service websites.

For European organizations, this vulnerability poses a significant risk, especially for businesses relying on WordPress-based e-commerce or service platforms that use the affected plugin. Successful exploitation could lead to full server compromise, data theft, defacement, or disruption of services, impacting customer trust and regulatory compliance, including GDPR mandates on data protection. The ability to execute arbitrary code remotely without authentication makes it a critical threat vector for cybercriminals targeting European SMEs and enterprises that often use WordPress plugins for business operations. The impact extends to potential lateral movement within networks, data exfiltration, and ransomware deployment. Given the high confidentiality, integrity, and availability impacts, organizations could face operational downtime, financial losses, and reputational damage.

Immediate mitigation steps include: 1) Identifying and inventorying all WordPress installations using the 'Request a Quote Form' plugin, particularly versions ≤ 2.5.2. 2) Temporarily disabling or removing the plugin until a security patch is available. 3) Implementing Web Application Firewall (WAF) rules to detect and block suspicious requests targeting the emd_form_builder_lite_pagenum function or unusual function invocation patterns. 4) Restricting access to the WordPress admin and plugin endpoints via IP whitelisting or VPN where feasible. 5) Monitoring server logs for anomalous function calls or unexpected behavior indicative of exploitation attempts. 6) Applying the patch promptly once released by the vendor. 7) Conducting a thorough security audit of WordPress environments to identify other potential injection points. 8) Employing runtime application self-protection (RASP) tools that can detect and prevent eval injection attacks dynamically. These measures go beyond generic advice by focusing on immediate containment, proactive detection, and environment hardening tailored to this specific eval injection vulnerability.