The Qi Blocks plugin for WordPress, developed by qodeinteractive, suffers from an improper access control vulnerability identified as CVE-2025-12182. The root cause is the absence of a capability check in the resize_image_callback() function, which is responsible for resizing images in the WordPress media library. This flaw allows any authenticated user with at least Contributor-level privileges to resize images uploaded by other users without verifying ownership or permissions. Since resizing images involves file manipulation and server-side processing, an attacker can exploit this to perform unauthorized file writes and consume significant server resources by forcing the processing of large images. This can lead to degraded server performance, potential denial of service conditions, and unintended modification of media assets. The vulnerability affects all versions of Qi Blocks up to and including 1.4.3. The CVSS 3.1 base score of 4.3 reflects a medium severity, with the attack vector being network-based, low attack complexity, requiring privileges, and no user interaction. The impact is limited to integrity and availability, as confidentiality is not affected. No patches or known exploits are currently available, but the vulnerability is publicly disclosed and should be addressed promptly to prevent abuse.

For European organizations, especially those relying on WordPress sites with multiple contributors and using the Qi Blocks plugin, this vulnerability can lead to unauthorized manipulation of media content and resource exhaustion. The ability for contributors to resize images they do not own can result in unintended file modifications, potentially disrupting website content integrity. Moreover, the processing of large images can cause excessive CPU and memory usage, leading to degraded website performance or outages, impacting availability. This is particularly critical for organizations hosting high-traffic websites or those with limited server resources. While no direct data confidentiality breach occurs, the integrity and availability impacts can affect user trust and operational continuity. Additionally, attackers could leverage this vulnerability as part of a broader attack chain to disrupt services or prepare for further exploitation. European entities with compliance obligations around service availability and content integrity should consider this a significant operational risk.

Organizations should immediately verify the version of the Qi Blocks plugin in use and upgrade to a patched version once available from the vendor. In the absence of an official patch, administrators can implement temporary mitigations such as restricting Contributor-level user capabilities to prevent image resizing or disabling the resize_image_callback() functionality via custom code or plugin modifications. Monitoring server resource usage and media library activity logs can help detect abnormal image processing patterns indicative of exploitation attempts. Employing Web Application Firewalls (WAFs) with rules to detect and block suspicious requests targeting the resize_image_callback() endpoint can reduce risk. Additionally, enforcing strict user role management and limiting the number of users with Contributor or higher privileges reduces the attack surface. Regular backups of media assets and website content are recommended to enable recovery from any unauthorized changes. Finally, organizations should stay informed about vendor updates and security advisories related to Qi Blocks.