Auth bypass in Masterstudy Lms WordPress Plugin

CVE-2026-81340

The MasterStudy LMS WordPress Plugin WordPress plugin before 3.7.50 does not perform per-object ownership or capability checks when updating orders through its REST API, allowing users with the Instructor role to modify any order on the site, granting free course enrolment, revoking other users' paid enrolments, and tampering with order notes.

Vulnerability class: IDOR (Insecure Direct Object Reference)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 3.8 (Low). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:L.

EPSS exploit prediction

EPSS: 0.003 (24.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 24.8% 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-2026-81340: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

  • Masterstudy Lms WordPress Plugin

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-81340?
CVE-2026-81340 is a low-severity vulnerability in Masterstudy Lms WordPress Plugin, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 3.8/10. Published 2026-09-18.
How severe is CVE-2026-81340?
Low severity. CVSS v3 base score is 3.8 out of 10.