CVE-2026-81026

MasterStudy LMS WordPress Plugin – for Online Courses and Education < 3.7.40 - Unauthenticated Payment Bypass

2026-08-27 00:00

Strategic Overview

Status: Patched in 3.7.40
Affected Plugin: MasterStudy LMS WordPress Plugin – for Online Courses and Education
Affected Version: < 3.7.40
CVSS: 5.3Medium
Weakness type: CWE-602 · Client-Side Enforcement of Server-Side Security
CVE: CVE-2026-81026

View all MasterStudy LMS WordPress Plugin – for Online Courses and Education vulnerabilities

At a glance

CVE-2026-81026 is a medium-severity Client-Side Enforcement of Server-Side Security vulnerability in the MasterStudy LMS WordPress Plugin WordPress plugin, affecting versions < 3.7.40. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 3.7.40; sites on affected versions should update now. Disclosed August 2026, reported by Abdullah Kareem.

Vulnerability Overview

The MasterStudy LMS WordPress Plugin – for Online Courses and Education plugin for WordPress is vulnerable to Payment Bypass in all versions up to 3.7.40 (exclusive). This is due to insufficient IPN verification. This makes it possible for unauthenticated attackers to bypass payments.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-602: Client-Side Enforcement of Server-Side Security

The product is composed of a server that relies on the client to implement a mechanism that is intended to protect the server.

Remediation

Update to version 3.7.40, or a newer patched version

How does WordSec protect against this?

This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. None of that substitutes for the fix: MasterStudy LMS WordPress Plugin 3.7.40 closes this, and updating the plugin is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-81026 https://www.wordfence.com/threat-intel/vulnerabilities/id/f09b6e61-ebfc-4213-8777-f133de66a30b https://nvd.nist.gov/vuln/detail/CVE-2026-81026

Related records

Other vulnerabilities in MasterStudy LMS WordPress Plugin – for Online Courses and Education

CVSS Vector

5.3

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityNone
IntegrityLow
AvailabilityNone

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