CVE-2026-39394 HIGH

CVE-2026-39394: CI4MS has an .env CRLF Injection via Unvalidated `host` Parameter in Install Controller

Vendor Ci4-Cms-Erp
Product ci4ms
Weakness CWE-93 · CRLF injection
Published April 8, 2026
Last update April 8, 2026

CVSS base score

8.1/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

What the vulnerability does

01Description

CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to 0.31.4.0, the Install::index() controller reads the host POST parameter without any validation and passes it directly into updateEnvSettings(), which writes it into the .env file via preg_replace(). Because newline characters in the value are not stripped, an attacker can inject arbitrary configuration directives into the .env file. The install routes have CSRF protection explicitly disabled, and the InstallFilter can be bypassed when cache('settings') is empty (cache expiry or fresh deployment). This vulnerability is fixed in 0.31.4.0.

Key dates

02Disclosure timeline

April 8, 2026 CVE published
April 8, 2026 Record updated