Improper Access Control in MasterStudy LMS WordPress Plugin
CVE-2026-81339

4.3MEDIUM

Key Information:

Vendor

WordPress
Status
Masterstudy Lms WordPress Plugin
Vendor
CVE Published:
23 September 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-81339?

The MasterStudy LMS WordPress Plugin prior to version 3.7.50 exhibits improper access control by failing to enforce per-object ownership checks. This flaw enables any authenticated user, even those with a subscriber role, to access quiz attempt results of other users. By exploiting this vulnerability, individuals can gain unauthorized visibility into fellow students' quiz grades, pass/fail statuses, and attempt timestamps by utilizing the attempt identifiers of other users.

Affected Version(s)

MasterStudy LMS WordPress Plugin 0 < 3.7.50

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-81339 - Proof of Concept

References

https://wpscan.com/vulnerability/f027d0b1-5d8a-4e80-adb3-...
exploitvdb-entrytechnical-description

CVSS V3.1

Score:
4.3
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Revanth Hari Narayana Matte
WPScan
.