Chamilo LMS is an open-source learning management system. In versions prior to 2.0.0-RC.3, a Stored Cross-Site Scripting (XSS) vulnerability exists in the social post attachment upload functionality, where an authenticated user can upload a malicious HTML file containing JavaScript via the /api/socialpostattachments endpoint. The uploaded file is served back from the application at the generated contentUrl without sanitization, content type restrictions, or a Content-Disposition: attachment header, causing the JavaScript to execute in the browser within the application's origin. Because the payload is stored server-side and runs in the trusted origin, an attacker can perform session hijacking, account takeover, privilege escalation (if an admin views the link), and arbitrary actions on behalf of the victim. This issue has been fixed in version 2.0.0-RC.3.

Chamilo LMS is an open-source learning management system. In versions prior to 2.0.0-RC.3, the PENS (Package Exchange Notification Services) plugin endpoint at public/plugin/Pens/pens.php is accessible without authentication and accepts a user-controlled package-url parameter that the server fetches using curl without filtering private or internal IP addresses, enabling unauthenticated Server-Side Request Forgery (SSRF). An attacker can exploit this to probe internal network services, access cloud metadata endpoints (such as 169.254.169.254) to steal IAM credentials and sensitive instance metadata, or trigger state-changing operations on internal services via the receipt and alerts callback parameters. No authentication is required to exploit either SSRF vector, significantly increasing the attack surface. This issue has been fixed in version 2.0.0-RC.3.

Chamilo LMS is an open-source learning management system. In versions prior to 2.0.0-RC.3, the /api/courserelusers 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.

Chamilo LMS is an open-source learning management system. In versions prior to 2.0.0-RC.3, the notebook module contains an Insecure Direct Object Reference (IDOR) vulnerability that allows any authenticated student to read the private course notes of any other user on the platform by manipulating the notebookid parameter in the editnote action. The application fetches the note content using only the supplied integer ID without verifying that the requesting user owns the note, and the full title and HTML body are rendered in the edit form and returned to the attacker's browser. While ownership checks exist in the write paths (updateNote() and deletenote()), they are entirely absent from the read path (getnoteinformation()). This issue has been fixed in version 2.0.0-RC.3.

Chamilo LMS is an open-source learning management system. In versions prior to 2.0.0-RC.3, an OS Command Injection vulnerability exists in the main/inc/ajax/gradebook.ajax.php endpoint within the exportallcertificates action, where the course code retrieved from the session variable $SESSION['cid'] via apigetcourseid() is concatenated directly into a shellexec() command string without sanitization or escaping using escapeshellarg(). If an attacker can manipulate or poison their session data to inject shell metacharacters into the cid variable, they can achieve arbitrary command execution on the underlying server. Successful exploitation grants full access to read system files and credentials, alters the application and database, or disrupts server availability. This issue has been fixed in version 2.0.0-RC.3.

Chamilo LMS is an open-source learning management system. In versions prior to 2.0.0-RC.3, an insecure direct object modification vulnerability in the PUT /api/users/{id} endpoint allows any authenticated user with ROLESTUDENT to escalate their privileges to ROLEADMIN by modifying the roles field on their own user record. The API Platform security expression isgranted('EDIT', object) only verifies record ownership, and the roles field is included in the writable serialization group, enabling any user to set arbitrary roles such as ROLEADMIN. Successful exploitation grants full administrative control of the platform, including access to all courses, user data, grades, and administrative settings. This issue has been fixed in version 2.0.0-RC.3.

Chamilo LMS is a learning management system. From 1.11.0 to 2.0-beta.1, anyone can trigger a malicious redirect through the use of the redirect parameter to /login. This vulnerability is fixed in 2.0-beta.2.

Chamilo LMS is a learning management system. Prior to 2.0.0-RC.3, an Insecure Direct Object Reference (IDOR) vulnerability in the REST API stats endpoint allows any authenticated user (including low-privilege students with ROLEUSER) to read any other user's learning progress, certificates, and gradebook scores for any course, without enrollment or supervisory relationship. This vulnerability is fixed in 2.0.0-RC.3.