What is CVE-2026-33737?

CVE-2026-33737 is a medium-severity vulnerability in Chamilo Chamilo-lms, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 5.3/10. Published 2026-04-10.

How severe is CVE-2026-33737?

Medium severity. CVSS v3 base score is 5.3 out of 10.

XXE in Chamilo Chamilo-lms

CVE-2026-33737

Chamilo LMS is a learning management system. Prior to 1.11.38 and 2.0.0-RC.3, multiple files use simplexml_load_string() without XXE protection. With LIBXML_NOENT flag, arbitrary server files can be read. This vulnerability is fixed in 1.1…

Vulnerability class: XXE (XML External Entity)

EPSS: 0.000 (11.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

Chamilo Chamilo-lms — versions < 1.11.38, >= 2.0.0-alpha.1, < 2.0.0-RC.3

Weakness classification (CWE)

CWE-611 — Improper Restriction of XML External Entity Reference (XXE)

References

https://github.com/chamilo/chamilo-lms/security/advisories/GHSA-c4ww-qgf2-v89j (x_refsource_CONFIRM)
https://github.com/chamilo/chamilo-lms/commit/22b1cb1c609b643765c88654155aba27070c927e (x_refsource_MISC)
https://github.com/chamilo/chamilo-lms/commit/af6b7002af7c15825e98fc522e2ead0d00cacaa3 (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-33737?: CVE-2026-33737 is a medium-severity vulnerability in Chamilo Chamilo-lms, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 5.3/10. Published 2026-04-10.
How severe is CVE-2026-33737?: Medium severity. CVSS v3 base score is 5.3 out of 10.