Deserialization of Untrusted Data in Chamilo LMS - CVE-2026-61538
Published: August 4, 2026
Vulnerability identifier: #VU140923
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-61538
CWE-ID: CWE-502
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to execute arbitrary code.
The vulnerability exists due to deserialization of untrusted data in the course-backup diagnose endpoint when processing an uploaded backup ZIP containing attacker-controlled course_info.dat data. A remote user can upload a crafted backup and trigger a PHP object injection gadget chain to execute arbitrary code.
If self-registration as teacher is enabled, exploitation may be reachable starting from an anonymous user.
Affected software
Chamilo LMS
How to mitigate CVE-2026-61538
Install security update from vendor's website.
Chamilo LMS - update to 2.0.3