Auth bypass in Chamilo Chamilo-Lms
CVE-2026-34370
Chamilo LMS is an open-source learning management system. In versions prior to 2.0.0-RC.3, the notebook module contains an Insecure Direct Object Reference (IDOR) vulnerability that allows any authenticated student to read the private course notes of any other user on the platform by manipulating the notebook_id parameter in the editnote action. The application fetches the note content using only the supplied integer ID without verifying that the requesting user owns the note, and the full title and HTML body are rendered in the edit form and returned to the attacker's browser. While ownership checks exist in the write paths (updateNote() and delete_note()), they are entirely absent from the read path (get_note_information()). This issue has been fixed in version 2.0.0-RC.3.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.004 (29.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 29.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.004 · change: +0.002
Affected products
- Chamilo Chamilo-Lms — versions < 2.0.0-RC.3
- Chamilo Lms — versions 2.0.0
Weakness classification (CWE)
References
- github.com/chamilo/chamilo-lms/security/advisories/GHSA-fm35-2hvw-564q (Vendor Advisory)
- github.com/chamilo/chamilo-lms/releases/tag/v2.0.0-RC.3 (Product, Release Notes)
Frequently asked questions
- What is CVE-2026-34370?
- CVE-2026-34370 is a medium-severity vulnerability in Chamilo Chamilo-Lms, classified under Improper Authorization. CVSS score: 6.5/10. Published 2026-04-14.
- How severe is CVE-2026-34370?
- Medium severity. CVSS v3 base score is 6.5 out of 10.