CVE-2026-34602
Chamilo LMS: IDOR in /api/course_rel_users Allows Unauthorized Enrollment of Arbitrary Users into Courses
CVE-2026-34602 is a high vulnerability (CVSS 7.1) in Chamilo Lms, published April 14, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.21%, the 11th percentile. No source names a fixed version.
- Severity
- 7.1 HighCVSS 3.1, CVE List
- Exploit chance
- 0.21%EPSS, 11th percentile
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
- No fix listedNo source names one
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- High
- Availability
- None
Exploit likelihood
Affected products
What each source reports
CVE List Score used
Chamilo LMS: IDOR in /api/course_rel_users Allows Unauthorized Enrollment of Arbitrary Users into Courses
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.
- Record
CVE-2026-34602- CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N - Weakness
- CWE-639
- Updated
- 2026-11-02
EUVDEUVD-2026-22718
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.
- Record
EUVD-2026-22718- CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N - Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-34602- CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N - Weakness
- CWE-639
- Updated
- 2026-11-02
OSV
Chamilo LMS: IDOR in /api/course_rel_users Allows Unauthorized Enrollment of Arbitrary Users into Courses
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.
- Record
CVE-2026-34602- CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N - Weakness
- CWE-639
- Updated
- 2026-11-11
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | OSV | |
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
References
github.com/chamilo/chamilo-lms/security/advisories/GHSA-x373-8j9j-g5pj
nvd.nist.gov/vuln/detail/CVE-2026-34602