CVE-2026-81339 (GCVE-0-2026-81339)
Vulnerability from cvelistv5 – Published: 2026-09-23 06:00 – Updated: 2026-09-23 10:59
VLAI
EPSS
VEX
Title
MasterStudy LMS < 3.7.50 - Subscriber+ Quiz Attempt Grade Disclosure via IDOR
Summary
The MasterStudy LMS WordPress Plugin WordPress plugin before 3.7.50 does not perform a per-object ownership check when returning a quiz attempt result, allowing any authenticated user with a minimal (subscriber) role to read other students' quiz grades, pass/fail status and attempt timestamps by referencing an attempt identifier belonging to another user.
Severity
4.3 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-23 10:46 UTC
CWE
- CWE-639 Authorization Bypass Through User-Controlled Key
- CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://wpscan.com/vulnerability/f027d0b1-5d8a-4e… | exploitvdb-entrytechnical-description |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Unknown | MasterStudy LMS WordPress Plugin |
Affected:
0 , < 3.7.50
(semver)
|
guessed |
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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They have not been verified by an analyst and are provided for guidance only.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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