5.3
MEDIUM CVSS 3.1
CVE-2026-5167
Masteriyo LMS <= 2.1.7 - Unauthenticated Authorization Bypass to Arbitrary Order Completion via Stripe Webhook Endpoint
Description

The Masteriyo LMS – Online Course Builder for eLearning, LMS & Education plugin for WordPress is vulnerable to Authorization Bypass Through User-Controlled Key in versions up to and including 2.1.7. This is due to insufficient webhook signature verification in the handle_webhook() function. The webhook endpoint processes unauthenticated requests and only performs signature verification if both the webhook_secret setting is configured AND the HTTP_STRIPE_SIGNATURE header is present. Since webhook_secret defaults to an empty string, the webhook processes attacker-controlled JSON payloads without any verification. This makes it possible for unauthenticated attackers to send fake Stripe webhook events with arbitrary order_id values in the metadata, mark any order as completed without payment, and gain unauthorized access to paid course content.

INFO

Published Date :

April 8, 2026, 7:16 a.m.

Last Modified :

April 8, 2026, 7:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-5167 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update Masteriyo LMS to patch authorization bypass via webhook signature verification.
  • Update Masteriyo LMS plugin to version 2.1.8 or later.
  • Ensure webhook secrets are properly configured.
  • Verify webhook signature validation logic.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-5167 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-5167 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-5167 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-5167 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Apr. 08, 2026

    Action Type Old Value New Value
    Added Description The Masteriyo LMS – Online Course Builder for eLearning, LMS & Education plugin for WordPress is vulnerable to Authorization Bypass Through User-Controlled Key in versions up to and including 2.1.7. This is due to insufficient webhook signature verification in the handle_webhook() function. The webhook endpoint processes unauthenticated requests and only performs signature verification if both the webhook_secret setting is configured AND the HTTP_STRIPE_SIGNATURE header is present. Since webhook_secret defaults to an empty string, the webhook processes attacker-controlled JSON payloads without any verification. This makes it possible for unauthenticated attackers to send fake Stripe webhook events with arbitrary order_id values in the metadata, mark any order as completed without payment, and gain unauthorized access to paid course content.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
    Added CWE CWE-639
    Added Reference https://plugins.trac.wordpress.org/browser/learning-management-system/tags/2.1.4/addons/stripe/StripeAddon.php#L563-639
    Added Reference https://plugins.trac.wordpress.org/browser/learning-management-system/tags/2.1.4/addons/stripe/StripeAddon.php#L649-704
    Added Reference https://plugins.trac.wordpress.org/browser/learning-management-system/trunk/addons/stripe/StripeAddon.php#L563-639
    Added Reference https://plugins.trac.wordpress.org/browser/learning-management-system/trunk/addons/stripe/StripeAddon.php#L649-704
    Added Reference https://plugins.trac.wordpress.org/changeset/3499458/learning-management-system/trunk/addons/stripe/StripeAddon.php
    Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/b6d51dc3-b695-4e9d-b25a-d1b302be1fec?source=cve
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.