CVE-2026-81339
📛 CVE Title
MasterStudy LMS < 3.7.50 - Subscriber+ Quiz Attempt Grade Disclosure via IDOR
Description
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.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- WPScan
- CVSS severity
- —
- CVSS score
- —
- CVSS vector
- —
- Effective score
- 4.3 / 10 MEDIUM source: NVD
- CWE(s)
-
CWE-639 Authorization Bypass Through User-Controlled Key - Reserved
- 2026-08-26
- Published
- 2026-09-23 06:00 UTC
- Last updated
- 2026-09-23 10:59 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/81xxx/CVE-2026-81339.json
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-09-23 06:17:02 UTC
- NVD last modified
- 2026-09-23 18:13:31 UTC
- NVD CVSS v3.1
- 4.3 / 10 MEDIUM source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N- Exploitability subscore
- 2.8 / 10
- Impact subscore
- 1.4 / 10
- EPSS score
- 0.0018 (probability of exploitation in next 30 days)
- EPSS percentile
- 7.86% vs all CVEs — higher = more likely to be exploited, as of 2026-09-23
NVD-assigned CWE(s):
CWE-639
(differs from the CNA list above)
NVD / KEV / EPSS data refreshed 2026-09-24 04:34 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-85029 - Assigner
- WPScan
- Published
- Sep 23, 2026, 6:00:15 AM
- Updated
- Sep 23, 2026, 10:59:07 AM
- EUVD base score (CVSS 3.1)
-
4.3 / 10
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N - EUVD-reported EPSS
- 0.1800
- Vendors
- Unknown
- Products
-
MasterStudy LMS WordPress Plugin (0 <3.7.50)
- Aliases
-
GHSA-fj8j-x93w-h29w
ENISA description: 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.
EUVD references (1)
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Unknown | MasterStudy LMS WordPress Plugin |
0 (affected)
|
— |
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
- https://wpscan.com/vulnerability/f027d0b1-5d8a-4e80-adb3-bbf97dc53306/ exploitvdb-entrytechnical-description
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
NVD-tagged references (1)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://wpscan.com/vulnerability/f027d0b1-5d8a-4e80-adb3-bbf97dc53306/ contact@wpscan.com
Remediations (10)
-
web:msrc.microsoft.com
The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.
2026-09-24 11:50 UTC -
web:msrc.microsoft.com
Security Update Guide - Microsoft Security Response Center
2026-09-24 11:50 UTC -
web:redis.io
Update 9/1/2026: Following further review, the public CVE record for CVE - 2026 -81934 was updated to reflect a revised CVSS score of 7.5 (High).
2026-09-24 11:50 UTC -
web:senserva.com
Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.
2026-09-24 11:50 UTC -
web:support.microsoft.com
Be aware that the update in the Microsoft Download Center applies to the Microsoft Installer (.msi)-based edition of Office 2016. It doesn't apply to the Office 2016 Click-to-Run editions, such as Microsoft Office 365 Home. (See What version of Office am I using?) How to get and install the update Method 1: Microsoft Update This update is available from Microsoft Update. When you turn on ...
2026-09-24 11:50 UTC -
web:vulmon.com
Vulnerability Summary MasterStudy LMS WordPress Plugin versions prior to 3.7.50 enable any authenticated user, even those with a subscriber role, to access other students' quiz results. This includes pass/fail status, grades, and attempt timestamps, by providing an attempt identifier belonging to another user. The vulnerability stems from a lack of per-object ownership checks when returning ...
2026-09-24 11:50 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-24 11:50 UTC -
web:www.oracle.com
This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-24 11:50 UTC -
web:www.theregister.com
If you use WordPress, patch now. Just hours after fixes came out, attackers have begun exploiting two bugs that, when chained together, allow pre-authentication remote code execution (RCE). And security researchers tell us there's a very good chance the miscreants had an AI assist. "Once the vulnerabilities were publicly disclosed, reproducing them with the help of frontier AI models was ...
2026-09-24 11:50 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's September 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-09-24 11:50 UTC
AI Forensic Analysis
Only Available for Registered Users. Sign in to view.
Raw JSON
The full cvelistV5 record. Download as CVE-2026-81339.json.
{
"containers": {
"adp": [
{
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 4.3,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "LOW",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
"version": "3.1"
}
},
{
"other": {
"content": {
"id": "CVE-2026-81339",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-09-23T10:46:57.286810Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-639",
"description": "CWE-639 Authorization Bypass Through User-Controlled Key",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-09-23T10:59:07.298Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "MasterStudy LMS WordPress Plugin",
"vendor": "Unknown",
"versions": [
{
"lessThan": "3.7.50",
"status": "affected",
"version": "0",
"versionType": "semver"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "finder",
"value": "Revanth Hari Narayana Matte"
},
{
"lang": "en",
"type": "coordinator",
"value": "WPScan"
}
],
"descriptions": [
{
"lang": "en",
"value": "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."
}
],
"problemTypes": [
{
"descriptions": [
{
"description": "CWE-639 Authorization Bypass Through User-Controlled Key",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-09-23T06:00:15.932Z",
"orgId": "1bfdd5d7-9bf6-4a53-96ea-42e2716d7a81",
"shortName": "WPScan"
},
"references": [
{
"tags": [
"exploit",
"vdb-entry",
"technical-description"
],
"url": "https://wpscan.com/vulnerability/f027d0b1-5d8a-4e80-adb3-bbf97dc53306/"
}
],
"source": {
"discovery": "EXTERNAL"
},
"title": "MasterStudy LMS < 3.7.50 - Subscriber+ Quiz Attempt Grade Disclosure via IDOR",
"x_generator": {
"engine": "WPScan CVE Generator"
}
}
},
"cveMetadata": {
"assignerOrgId": "1bfdd5d7-9bf6-4a53-96ea-42e2716d7a81",
"assignerShortName": "WPScan",
"cveId": "CVE-2026-81339",
"datePublished": "2026-09-23T06:00:15.932Z",
"dateReserved": "2026-08-26T18:07:09.452Z",
"dateUpdated": "2026-09-23T10:59:07.298Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}