Vulnerability · Published Apr 10, 2026 · Assigned by GitHub_M

CVE-2026-33704Chamilo LMS Affected by Authenticated Arbitrary File Write via BigUpload endpoint

High 7.1

In plain English

A high-severity unrestricted file upload in chamilo-lms from chamilo. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 37% of all known vulnerabilities).

Severity (CVSS 3.1)7.1High

Exploit odds (30 days)0.4%top 63.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Chamilo LMS is a learning management system. Prior to 1.11.38, any authenticated user (including students) can write arbitrary content to files on the server via the BigUpload endpoint. The key parameter controls the filename and the raw POST body becomes the file content. While .php extensions are filtered to .phps, the .pht extension passes through unmodified. On Apache configurations where .pht is handled as PHP, this leads to Remote Code Execution. This vulnerability is fixed in 1.11.38.

Affected products (as reported)

Vendor	Product	Versions
chamilo	chamilo-lms	< 1.11.38

Weakness: CWE-434 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

References

https://github.com/chamilo/chamilo-lms/security/advisories/GHSA-phfx-pwwg-945v x_refsource_CONFIRM
https://github.com/chamilo/chamilo-lms/commit/9748f1ffbdb8b6dc84c0e0591c9d3c1d92e21c00 x_refsource_MISC