XSS in Masteriyo Lms

CVE-2026-19712

The Masteriyo LMS WordPress plugin before 2.3.3 does not sanitise and escape a quiz field before outputting it back in a page, and grants its instructor role the ability to store unfiltered HTML, allowing such users to perform Stored Cross-Site Scripting attacks against any visitor of the affected page, including administrators. This affects default single-site installations. Sites running multisite, or defining DISALLOW_UNFILTERED_HTML, are not affected as the capability is not granted there.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (15.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 15.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-19712: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

  • Masteriyo Lms — versions 0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-19712?
CVE-2026-19712 is a medium-severity vulnerability in Masteriyo Lms, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-08-16.
How severe is CVE-2026-19712?
Medium severity. CVSS v3 base score is 6.1 out of 10.