SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-5167

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.

MEDIUM 5.3EPSS 0.38%

Does this matter?

Lower severity and a low EPSS score (0.38%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.1
5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS
0.38% probability · 31th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-639
Source
security@wordfence.com
EPSS trend
0%3%5%26 October 2026: 0.38%26 October 202626 October 2026

EPSS 0.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.