LearnPress 4.3.3 Stored XSS via skin attribute
CVE-2026-4333 Published on April 8, 2026
LearnPress <= 4.3.3 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'skin' Shortcode Attribute
The LearnPress WordPress LMS Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'skin' attribute of the learn_press_courses shortcode in all versions up to and including 4.3.3. This is due to insufficient input sanitization and output escaping on the 'skin' shortcode attribute. The attribute value is used directly in an sprintf() call that generates HTML (class attribute and data-layout attribute) without any esc_attr() escaping. 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.
Timeline
Vendor Notified
Disclosed 21 days later.
Weakness Type
What is a XSS Vulnerability?
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
CVE-2026-4333 has been classified to as a XSS vulnerability or weakness.
Products Associated with CVE-2026-4333
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Affected Versions
thimpress LearnPress – WordPress LMS Plugin for Create and Sell Online Courses:- Before and including 4.3.3 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.