CVE-2025-11867 describes a stored cross-site scripting vulnerability in the Bg Book Publisher WordPress plugin (all versions up to 1.25). The vulnerability occurs because the plugin fails to properly escape the book_author post meta value before rendering it through the [book_author] shortcode. This allows authenticated users with contributor or higher privileges to inject arbitrary JavaScript code that executes in the context of any user viewing the injected page. The CVSS 3.1 vector (AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N) reflects network attack vector, low attack complexity, requiring privileges, no user interaction, scope changed, with low confidentiality and integrity impact and no availability impact.

Successful exploitation allows an attacker with contributor-level access or higher to inject persistent malicious scripts into pages via the book_author meta field. These scripts execute in the browsers of users who view the affected pages, potentially leading to session hijacking, defacement, or other client-side attacks. The impact affects confidentiality and integrity but does not affect availability. There are no known exploits in the wild at this time.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, restrict contributor-level access to trusted users only and consider removing or disabling the Bg Book Publisher plugin if possible. Avoid using the [book_author] shortcode with untrusted input. Monitor vendor channels for updates and apply patches promptly once available.