Chamilo LMS has Reflected XSS via Unsanitized http_build_query() in Exercise Question List Pagination

published 2026-04-10 6 mo ago modified 2026-10-26 13 d ago also EUVD-2026-21525

cvss: 5.4; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.1%; EPSS 0.1% chance of exploitation in 30 days, percentile 3%
public exploits: 0; none known

Chamilo LMS is a learning management system. Prior to 2.0.0-RC.3, a Reflected Cross-Site Scripting (XSS) vulnerability in the exercise question list admin panel allows an attacker to execute arbitrary JavaScript in an authenticated teacher's browser. The pagination code merges all $_GET parameters via array_merge() and outputs the result via http_build_query() directly into HTML href attributes without htmlspecialchars() encoding. This vulnerability is fixed in 2.0.0-RC.3.

Patch / fix

fixed in 2 links 1

chamilo chamilo 2.0.0-rc.3
chamilo chamilo_lms 2.0.0-rc.3

github.com/chamilo/chamilo-lms@72bc403 commit

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 6 mo ago (2026-04-15)

Exploit prediction

0.15% chance of exploitation in the next 30 days, higher than 3% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.4	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Affected products

chamilo chamilo-lms

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

CVE List CVE-2026-32893
NVD CVE-2026-32893

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary