CVE-2026-0559: MasterStudy LMS WordPress Plugin – for Online Courses and Education <= 3.7.11 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'stm_lms_courses_grid_display' Shortcode
The MasterStudy LMS WordPress Plugin – for Online Courses and Education plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'stmlmscoursesgriddisplay' shortcode in all versions up to, and including, 3.7.11 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-0559?
CVE-2026-0559 is considered a high-severity vulnerability due to its potential for stored cross-site scripting attacks.
How do I fix CVE-2026-0559?
To fix CVE-2026-0559, update the MasterStudy LMS WordPress plugin to version 3.7.12 or later.
Who is affected by CVE-2026-0559?
CVE-2026-0559 affects all installations of the MasterStudy LMS WordPress plugin version 3.7.11 and earlier.
What type of vulnerability is CVE-2026-0559?
CVE-2026-0559 is a stored cross-site scripting vulnerability occurring via the 'stm_lms_courses_grid_display' shortcode.
What actions can be taken to mitigate CVE-2026-0559 before a fix is applied?
As a temporary mitigation for CVE-2026-0559, limit user access to roles below Contributor+ and sanitize any user-generated content.