CVE-2023-3533: Chamilo LMS Unauthenticated Remote Code Execution via Arbitrary File Write

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2023-11-28 · updated 2026-06-17
Weakness: CWE-22

Description

Path traversal in file upload functionality in `/main/webservices/additional_webservices.php` in Chamilo LMS <= v1.11.20 allows unauthenticated attackers to perform stored cross-site scripting attacks and obtain remote code execution via arbitrary file write.

Affected products

Chamilo: through 1.11.20

References

https://github.com/chamilo/chamilo-lms/commit/37be9ce7243a30259047dd4517c48ff8b21d657a
https://starlabs.sg/advisories/23/23-3533/
https://support.chamilo.org/projects/chamilo-18/wiki/security_issues#Issue-124-2023-07-13-Critical-impact-High-risk-Unauthenticated-Arbitrary-File-Write-RCE-CVE-2023-3533
https://github.com/chamilo/chamilo-lms/commit/37be9ce7243a30259047dd4517c48ff8b21d657a
https://starlabs.sg/advisories/23/23-3533/
https://support.chamilo.org/projects/chamilo-18/wiki/security_issues#Issue-124-2023-07-13-Critical-impact-High-risk-Unauthenticated-Arbitrary-File-Write-RCE-CVE-2023-3533

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