8.1
HIGH CVSS 3.1
CVE-2026-39393
Post-Installation Re-entry via Cache-Dependent Install Guard Bypass in ci4ms
Description

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 route guard in ci4ms relies solely on a volatile cache check (cache('settings')) combined with .env file existence to block post-installation access to the setup wizard. When the database is temporarily unreachable during a cache miss (TTL expiry or admin-triggered cache clear), the guard fails open, allowing an unauthenticated attacker to overwrite the .env file with attacker-controlled database credentials, achieving full application takeover. This vulnerability is fixed in 0.31.4.0.

INFO

Published Date :

April 8, 2026, 3:16 p.m.

Last Modified :

April 8, 2026, 3:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-39393 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update CI4MS to version 0.31.4.0 or later to fix the installation route guard vulnerability.
  • Update CI4MS to version 0.31.4.0.
  • Verify installation route guard functionality.
  • Monitor application for unauthorized access attempts.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-39393.

URL Resource
https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-8rh5-4mvx-xj7j
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-39393 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-39393 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-39393 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Apr. 08, 2026

    Action Type Old Value New Value
    Added Description 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 route guard in ci4ms relies solely on a volatile cache check (cache('settings')) combined with .env file existence to block post-installation access to the setup wizard. When the database is temporarily unreachable during a cache miss (TTL expiry or admin-triggered cache clear), the guard fails open, allowing an unauthenticated attacker to overwrite the .env file with attacker-controlled database credentials, achieving full application takeover. This vulnerability is fixed in 0.31.4.0.
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-306
    Added Reference https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-8rh5-4mvx-xj7j
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.