CVE-2025-8567: 
WordPress vulnerability analysis and mitigation

The Nexter Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting (XSS) in versions up to and including 4.5.4. The vulnerability was disclosed on August 19, 2025, and affects multiple widgets within the plugin. This security issue stems from insufficient input sanitization and output escaping on user-supplied attributes (NVD).

The vulnerability has been assigned a CVSS v3.1 base score of 6.4 (Medium) with the vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N. The attack requires network access and low privileges but no user interaction. The vulnerability is classified as CWE-79: Improper Neutralization of Input During Web Page Generation (Wordfence).

When exploited, this vulnerability allows authenticated attackers with contributor-level access or higher to inject arbitrary web scripts into pages. These malicious scripts will execute whenever a user accesses the affected page, potentially compromising user data or performing unauthorized actions on behalf of visitors (NVD).

The vulnerability has been patched in version 4.5.5 of the Nexter Blocks plugin. Users are strongly advised to update to this latest version to protect against potential XSS attacks (WordPress Plugin).