Chamilo LMS is an open-source learning management system. In version 2.0-RC.2, the file public/main/inc/ajax/install.ajax.php is accessible without authentication on fully installed instances because, unlike other AJAX endpoints, it does not include the global.inc.php file that performs authentication and installation-completed checks. Its test_mailer action accepts an arbitrary Symfony Mailer DSN string from POST data and uses it to connect to an attacker-specified SMTP server, enabling Server-Side Request Forgery (SSRF) into internal networks via the SMTP protocol. An unauthenticated attacker can also abuse this to weaponize the Chamilo server as an open email relay for phishing and spam campaigns, with emails appearing to originate from the server's IP address. Additionally, error responses from failed SMTP connections may disclose information about internal network topology and running services. This issue has been fixed in version 2.0.0-RC.3.

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Tue, 14 Apr 2026 21:15:00 +0000

Type Values Removed Values Added
Description Chamilo LMS is an open-source learning management system. In version 2.0-RC.2, the file public/main/inc/ajax/install.ajax.php is accessible without authentication on fully installed instances because, unlike other AJAX endpoints, it does not include the global.inc.php file that performs authentication and installation-completed checks. Its test_mailer action accepts an arbitrary Symfony Mailer DSN string from POST data and uses it to connect to an attacker-specified SMTP server, enabling Server-Side Request Forgery (SSRF) into internal networks via the SMTP protocol. An unauthenticated attacker can also abuse this to weaponize the Chamilo server as an open email relay for phishing and spam campaigns, with emails appearing to originate from the server's IP address. Additionally, error responses from failed SMTP connections may disclose information about internal network topology and running services. This issue has been fixed in version 2.0.0-RC.3.
Title Chamilo LMS has Unauthenticated SSRF and Open Email Relay via install.ajax.php test_mailer action
Weaknesses CWE-306
CWE-918
References
Metrics cvssV3_1

{'score': 7.2, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-04-14T21:05:35.043Z

Reserved: 2026-03-23T17:06:05.748Z

Link: CVE-2026-33715

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-04-14T21:16:26.060

Modified: 2026-04-14T21:16:26.060

Link: CVE-2026-33715

cve-icon Redhat

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cve-icon OpenCVE Enrichment

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Weaknesses