CVE-2026-31940: Session Fixation in Chamilo LMS

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-04-10 · updated 2026-10-26
Weakness: CWE-384

Description

Chamilo LMS is a learning management system. Prior to 1.11.38 and 2.0.0-RC.3, in main/lp/aicc_hacp.php, user-controlled request parameters are directly used to set the PHP session ID before loading global bootstrap. This leads to session fixation. This vulnerability is fixed in 1.11.38 and 2.0.0-RC.3.

Affected products

chamilo-lms: before 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) — fixed in 1.11.38

How to fix

Upgrade to a fixed version: chamilo-lms 1.11.38. Check the vendor advisory for mitigations.

References

https://github.com/chamilo/chamilo-lms/commit/ce0192c62e48c9d9474d915c541b3274844afbf9
https://github.com/chamilo/chamilo-lms/commit/e337b7cc74a0276a0b4f91f9282204d20cac1869
https://github.com/chamilo/chamilo-lms/security/advisories/GHSA-4gp7-cfjh-77gv

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