Authorization bypass through user-controlled key in Chamilo LMS - CVE-2026-34602
Published: April 24, 2026
Vulnerability identifier: #VU127569
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-34602
CWE-ID: CWE-639
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Chamilo
Affected software:
Chamilo LMS
Chamilo LMS
Detailed vulnerability description
The vulnerability allows a remote user to enroll arbitrary users into courses.
The vulnerability exists due to improper access control in the /api/course_rel_users endpoint when handling crafted POST requests that modify the user parameter in the request body. A remote user can send a specially crafted request to enroll arbitrary users into courses.
This can manipulate user-course relationships and may expose course materials to unintended users.
How to mitigate CVE-2026-34602
Install security update from vendor's website.