Chamilo LMS: IDOR in /api/course_rel_users Allows Unauthorized Enrollment of Arbitrary Users into Courses
Summary
| CVE | CVE-2026-34602 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-04-14 22:16:31 UTC |
| Updated | 2026-04-22 18:46:22 UTC |
| Description | Chamilo LMS is an open-source learning management system. In versions prior to 2.0.0-RC.3, the /api/course_rel_users endpoint is vulnerable to Insecure Direct Object Reference (IDOR), allowing an authenticated attacker to modify the user parameter in the request body to enroll any arbitrary user into any course without proper authorization checks. The backend trusts the user-supplied input for the user field and performs no server-side verification that the requester owns the referenced user ID or has permission to act on behalf of other users. This enables unauthorized manipulation of user-course relationships, potentially granting unintended access to course materials, bypassing enrollment controls, and compromising platform integrity. This issue has been fixed in version 2.0.0-RC.3. |
Risk And Classification
Primary CVSS: v3.1 7.1 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
EPSS: 0.000320000 probability, percentile 0.091750000 (date 2026-04-22)
Problem Types: CWE-639 | CWE-639 CWE-639: Authorization Bypass Through User-Controlled Key
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 7.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N |
| 3.1 | CNA | DECLARED | 7.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
LowIntegrity
HighAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Chamilo | Chamilo Lms | 2.0.0 | alpha1 | All | All |
| Application | Chamilo | Chamilo Lms | 2.0.0 | alpha2 | All | All |
| Application | Chamilo | Chamilo Lms | 2.0.0 | alpha3 | All | All |
| Application | Chamilo | Chamilo Lms | 2.0.0 | alpha4 | All | All |
| Application | Chamilo | Chamilo Lms | 2.0.0 | alpha5 | All | All |
| Application | Chamilo | Chamilo Lms | 2.0.0 | beta1 | All | All |
| Application | Chamilo | Chamilo Lms | 2.0.0 | beta2 | All | All |
| Application | Chamilo | Chamilo Lms | 2.0.0 | beta3 | All | All |
| Application | Chamilo | Chamilo Lms | 2.0.0 | rc1 | All | All |
| Application | Chamilo | Chamilo Lms | 2.0.0 | rc2 | All | All |
| Application | Chamilo | Chamilo Lms | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Chamilo | Chamilo-lms | affected < 2.0.0-RC.3 | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/chamilo/chamilo-lms/releases/tag/v2.0.0-RC.3 | [email protected] | github.com | Product, Release Notes |
| github.com/chamilo/chamilo-lms/security/advisories/GHSA-x373-8j9j-g5pj | [email protected] | github.com | Vendor Advisory |
| github.com/chamilo/chamilo-lms/commit/c9c30cdc48afae57cd6ab012ae2eceafd3... | [email protected] | github.com | Patch |
| github.com/chamilo/chamilo-lms/commit/2a9f060fa9d50fc9a92ed93af774d26196... | [email protected] | github.com | Patch |
| github.com/chamilo/chamilo-lms/commit/bd2ba34c2e74475587e38c74c90c2934e6... | [email protected] | github.com | Patch |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.