CVE-2025-11378 is a vulnerability classified under CWE-862 (Missing Authorization) affecting the ShortPixel Image Optimizer – Optimize Images, Convert WebP & AVIF WordPress plugin. The issue stems from the absence of a proper capability check on the 'shortpixel_ajaxRequest' AJAX action, which is responsible for handling export and import operations of site options. This flaw allows any authenticated user with Contributor-level permissions or higher to execute these actions without the necessary authorization, potentially leading to unauthorized modification of site configuration data. The vulnerability affects all versions up to and including 6.3.4 of the plugin. The CVSS v3.1 base score is 5.4 (medium), reflecting that the attack vector is network-based, requires low attack complexity, and privileges at the level of an authenticated user with limited rights, but no user interaction is needed. The impact primarily concerns confidentiality and integrity, as unauthorized users can export sensitive site options and import potentially malicious configurations, though availability is not affected. No public exploits have been reported yet, but the vulnerability presents a risk especially in environments where Contributor-level access is granted to multiple users or where user role management is lax. The plugin is widely used in WordPress sites for image optimization, making the scope of affected systems potentially large. The vulnerability was published on October 18, 2025, and no patches were listed at the time of reporting, emphasizing the need for immediate mitigation steps.

For European organizations, this vulnerability poses a risk to the integrity and confidentiality of WordPress sites using the ShortPixel Image Optimizer plugin. Unauthorized export and import of site options could lead to leakage of sensitive configuration data or unauthorized changes that may weaken site security or functionality. Organizations with multiple contributors or editors on their WordPress sites are particularly vulnerable, as these roles can exploit the flaw. This could result in data exposure, configuration tampering, or preparation for further attacks such as privilege escalation or site defacement. Given the widespread use of WordPress across Europe, especially in small and medium enterprises and digital agencies, the potential impact is significant. However, the lack of known exploits in the wild and the requirement for authenticated access somewhat limit the immediacy of the threat. Still, failure to address this vulnerability could lead to compliance issues under GDPR if personal data is exposed or integrity of data is compromised.

European organizations should implement the following specific mitigations: 1) Immediately audit user roles and permissions within WordPress to ensure that Contributor-level access is granted only to trusted users; 2) Restrict the number of users with Contributor or higher privileges to minimize attack surface; 3) Monitor and log AJAX requests to detect unusual activity related to 'shortpixel_ajaxRequest'; 4) Apply principle of least privilege by reviewing and tightening capabilities assigned to user roles; 5) Temporarily disable or remove the ShortPixel Image Optimizer plugin if feasible until a patch is released; 6) Follow vendor announcements closely and apply security patches as soon as they become available; 7) Employ Web Application Firewalls (WAFs) with rules to detect and block unauthorized AJAX requests targeting the vulnerable action; 8) Conduct regular security assessments and penetration tests focusing on WordPress plugins and user role management; 9) Educate site administrators and contributors about the risks of unauthorized access and the importance of secure credential management.