CVE-2026-100193 Tutor LMS <= 4.1.0 - Reflected Cross-Site Scripting via 'tab' Parameter
Unauthenticated attackers can inject arbitrary scripts via the tab parameter in Tutor LMS, requiring user interaction to execute.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-100193?
CVE-2026-100193 is a medium-severity cross-site scripting vulnerability in themeum Tutor LMS – eLearning and online course solution, published on 14 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
The Tutor LMS – eLearning and online course solution plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'tab' parameter in all versions up to, and including, 4.1.0 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. Exploitation requires the targeted lesson page to have an empty nav-items array — a condition that occurs naturally when a lesson has no post content, no attachments, and comments are disabled or the viewer is not logged in — which bypasses the in_array() tab validation and allows the raw attacker-controlled value to reach the sink.
Weakness: CWE-79
Which versions are affected by CVE-2026-100193?
How do I fix CVE-2026-100193?
No fix has been published for CVE-2026-100193 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-100193 being exploited?
There is no known exploitation of CVE-2026-100193 in the wild and no public exploit code.
Sources
Also known as GHSA-4vgh-wm7j-x4jg.