CVE-2026-40291: Chamilo LMS has Privilege Escalation via API User Role Modification

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-04-14 · updated 2026-07-24
Weakness: CWE-269

Description

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 ROLE_STUDENT to escalate their privileges to ROLE_ADMIN by modifying the roles field on their own user record. The API Platform security expression is_granted('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 ROLE_ADMIN. 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.

Affected products

chamilo-lms: through 1.11.38; 2.0.0-alpha1, 2.0.0-alpha2, 2.0.0-alpha3, 2.0.0-alpha4, 2.0.0-alpha5, 2.0.0-beta1 (+4)

References

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