The vulnerability identified as CVE-2025-11170 affects the WP移行専用プラグイン for CPI, a WordPress plugin developed by kddiwebcommunications. This plugin suffers from a lack of proper file type validation in the import function (Cpiwm_Import_Controller::import), allowing unauthenticated attackers to upload arbitrary files to the server. Because the plugin does not restrict or verify the file types being uploaded, attackers can upload malicious scripts or executables, potentially leading to remote code execution (RCE). The vulnerability is present in all versions up to and including 1.0.2. The CVSS 3.1 score of 9.8 reflects the critical nature of this flaw: it can be exploited remotely over the network without any authentication or user interaction, and it impacts confidentiality, integrity, and availability of the affected systems. Although no public exploits have been reported yet, the straightforward exploitation path and the common use of WordPress make this a high-risk vulnerability. The CWE-434 classification highlights the core issue as unrestricted file upload, a common vector for web application compromise. The plugin is primarily used for WordPress migration related to CPI hosting services, which may be niche but still relevant for affected users. The lack of available patches at the time of publication necessitates immediate risk mitigation steps.

For European organizations, this vulnerability poses a severe risk, especially those running WordPress sites that utilize the WP移行専用プラグイン for CPI plugin. Successful exploitation could lead to full server compromise, data breaches, defacement, or use of the server as a pivot point for further attacks. Confidential data stored or processed by the affected WordPress sites could be exposed or altered, and service availability could be disrupted by malicious payloads or ransomware. Given the plugin’s role in migration, organizations performing site transitions or backups with this plugin are particularly vulnerable. The impact extends beyond individual sites, as compromised servers can be used to launch attacks on other internal systems or external targets. The critical CVSS score underscores the urgency for European entities to assess their exposure and implement mitigations. Additionally, the lack of authentication and user interaction requirements lowers the barrier for attackers, increasing the likelihood of exploitation attempts.

1. Immediately identify and inventory all WordPress installations using the WP移行専用プラグイン for CPI plugin. 2. Disable or remove the plugin until a secure patched version is released. 3. Implement strict file upload validation at the web server or application firewall level, restricting allowed file types and scanning uploads for malicious content. 4. Monitor web server logs and file system changes for suspicious activity indicative of exploitation attempts. 5. Employ web application firewalls (WAFs) with rules targeting arbitrary file upload attempts. 6. Harden WordPress installations by limiting file permissions and disabling execution in upload directories. 7. Educate administrators about the risks of installing unverified plugins and the importance of timely updates. 8. Prepare incident response plans to quickly address potential compromises stemming from this vulnerability. 9. Follow vendor communications for patch releases and apply updates promptly once available.