CVE-2026-5167 Masteriyo LMS <= 2.1.7 - Unauthenticated Authorization Bypass to Arbitrary Order Completion via Stripe Webhook Endpoint
Unauthenticated attackers can bypass Stripe webhook verification to mark orders as paid, gaining unauthorized access to premium course content.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-5167?
CVE-2026-5167 is a medium-severity authentication bypass vulnerability in Masteriyo LMS – Online Course Builder for eLearning, LMS & Education, published on 8 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-639
Which versions are affected by CVE-2026-5167?
How do I fix CVE-2026-5167?
No fix has been published for CVE-2026-5167 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-5167 being exploited?
There is no known exploitation of CVE-2026-5167 in the wild and no public exploit code.
Sources
Also known as GHSA-v3v2-w9v8-q7h6.