CVE-2025-67944 is a critical vulnerability classified as 'Improper Control of Generation of Code' or code injection within the Nelio AB Testing plugin developed by Nelio Software. This plugin is widely used for A/B testing on WordPress websites. The vulnerability affects all versions up to and including 8.1.8. It allows an attacker with authenticated access and low privileges to inject arbitrary code remotely, which can be executed on the server. The CVSS v3.1 base score is 9.1, indicating a critical severity level, with the vector AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L. This means the attack can be performed over the network with low attack complexity, requiring low privileges but no user interaction, and it impacts confidentiality heavily, with partial impacts on integrity and availability. The vulnerability's scope is changed, indicating that the attack can affect resources beyond the initially vulnerable component. Although no known exploits are currently reported in the wild, the nature of the vulnerability makes it a high-value target for attackers seeking to compromise websites, steal sensitive data, or disrupt services. The lack of available patches at the time of reporting increases the urgency for mitigation and monitoring.

European organizations using Nelio AB Testing for WordPress A/B testing face significant risks from this vulnerability. Successful exploitation can lead to unauthorized code execution on web servers, resulting in data breaches, defacement, or service outages. Confidential information such as user data, credentials, and business intelligence could be exposed or manipulated. The integrity of website content and analytics can be compromised, undermining business decisions based on A/B testing results. Availability may be affected if attackers deploy denial-of-service payloads or disrupt plugin functionality. Given the widespread use of WordPress in Europe, especially among e-commerce, media, and marketing sectors, the impact could be broad and severe. Organizations with strict data protection regulations, such as GDPR, may face legal and financial consequences if breaches occur. The vulnerability's exploitation could also serve as a foothold for further lateral movement within corporate networks.

1. Immediately restrict access to the Nelio AB Testing plugin to only trusted and necessary users, minimizing the risk of authenticated exploitation. 2. Monitor web server and application logs for unusual or unauthorized code execution patterns, especially from users with low privileges. 3. Implement web application firewalls (WAF) with custom rules to detect and block suspicious payloads targeting the plugin. 4. Apply principle of least privilege on WordPress user roles to limit the ability to interact with the plugin. 5. Stay alert for official patches or updates from Nelio Software and apply them promptly once released. 6. Conduct regular security audits and vulnerability scans focusing on WordPress plugins and their configurations. 7. Consider temporary disabling the plugin if it is not critical to operations until a patch is available. 8. Educate administrators and developers about the risks of code injection and safe plugin management practices. 9. Use intrusion detection systems to identify potential exploitation attempts in real-time. 10. Backup website data and configurations regularly to enable quick recovery in case of compromise.