XSS in Chamilo Chamilo-Lms

CVE-2026-45143

Chamilo LMS is an open-source learning management system. From 2.0.0 through at least 2.1.0, Chamilo LMS stores private Message.content without server-side sanitization and renders it as HTML in assets/vue/views/message/MessageShow.vue and public/main/template/default/message/view_message.html.twig. An authenticated low-privilege user, including a student, can directly address crafted message content to an administrator because the message creation flow permits a sender to select another user as the recipient. The content executes in the recipient's browser when the recipient opens the routine inbox or message view, without requiring a link click, and can expose session credentials or permit actions as the administrator. This vulnerability is fixed in 2.0.1.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.005 (42.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-45143: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-45143?
CVE-2026-45143 is a critical-severity vulnerability in Chamilo Chamilo-Lms, classified under Cross-site Scripting. CVSS score: 9.0/10. Published 2026-09-17.
How severe is CVE-2026-45143?
Critical severity. CVSS v3 base score is 9.0 out of 10.