Authorization bypass through user-controlled key in Chamilo LMS - CVE-2026-61734

 

Authorization bypass through user-controlled key in Chamilo LMS - CVE-2026-61734

Published: August 4, 2026


Vulnerability identifier: #VU140928
CSH Severity: Low
CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-61734
CWE-ID: CWE-639
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote user to read other users' Web Push secrets, hijack Web Push notifications, and delete push subscriptions to cause a denial of service.

The vulnerability exists due to improper authorization and improperly controlled modification of dynamically-determined object attributes in the /api/push_subscriptions endpoint when handling authenticated API requests. A remote user can supply another user's identifier in the request body or access another user's subscription object to read sensitive fields, re-route notifications to an attacker-controlled endpoint, or delete another user's subscription to read other users' Web Push secrets, hijack Web Push notifications, and delete push subscriptions to cause a denial of service.

Exploitation can expose cryptographic Web Push material including endpoint, publicKey, and authToken, and can affect private messages, MFA codes, password-reset links, and course announcements delivered through the Web Push feature.


Affected software

Chamilo LMS

How to mitigate CVE-2026-61734

Install security update from vendor's website.

Chamilo LMS - update to 2.0.3

External References