Vulnerability · Published Oct 19, 2026 · Assigned by VulnCheck

CVE-2026-112329Sensei LMS 4.26.4 Broken Access Control via save_new_message

Medium 4.3

In plain English

A medium-severity missing authorization in Sensei LMS from Automattic. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 8% of all known vulnerabilities).

Severity (CVSS 3.1)4.3Medium

Exploit odds (30 days)0.2%top 92.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

The Sensei LMS WordPress plugin before 4.26.4 contains a broken access control vulnerability in the legacy save_new_message handler hooked on the init action, which validates only a generic nonce without verifying course enrollment or restricting post_id to valid post types. Authenticated attackers, including unprivileged Subscribers, can supply an arbitrary post_id for any course, lesson, or quiz to create a private message addressed to that post's author, bypassing the enrollment checks enforced by the newer REST send-message controller.

Affected products (as reported)

Vendor	Product	Versions
Automattic	Sensei LMS	0 – before 4.26.4

Weakness: CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

References

Release Notes release-notes, patch
VulnCheck Advisory: Sensei LMS 4.26.4 Broken Access Control via save_new_message third-party-advisory