CVE-2026-42878

An unauthenticated information disclosure vulnerability in the Installer controller allows any remote attacker to trigger phpinfo() on a fresh FacturaScripts deployment by requesting /?phpinfo=TRUE, exposing full PHP configuration, server environment variables (including any database credentials, API keys, or application secrets set as env vars), filesystem paths, and loaded extensions without being authenticated.

Details

The phpinfo() debug endpoint was intentionally added in commit 8c31c106 ("Added phpinfo option to the installer") on February 27, 2018, and has remained in the codebase for over 8 years across multiple major versions.

The feature appears to have been added as a convenience tool to help users diagnose PHP configuration during installation. However, it exposes sensitive server information to any unauthenticated attacker who knows the parameter.

Vulnerable code (Core/Controller/Installer.php ~line 115):

if ('TRUE' === $this->request->query('phpinfo', '')) {
    phpinfo();
    return;
}

This vulnerability is of the same class as CVE-2025-34081 (CONPROSYS HMI System unauthenticated phpinfo() exposure), which received a CVE assignment.

Introduced: commit 8c31c1060581ad6ad591c7689da3a8df8a29f486 (Feb 27 2018)
Still present: v2026-39-g262e79208 (confirmed April 2026)

PoC

Prerequisites: Fresh FacturaScripts deployment where installation has not yet been completed (config.php does not contain db_name).

Step 1, Clone and serve the application:
git clone https://github.com/NeoRazorX/facturascripts
cd facturascripts
php -S localhost:8000

Step 2, Send the following unauthenticated GET request:
GET /?phpinfo=TRUE HTTP/1.1
Host: localhost:8000

Step 3, Observe full phpinfo() output returned (20+ pages) containing:
- Complete PHP configuration
- All server environment variables
- Filesystem paths
- Loaded extensions and versions
- HTTP request headers

No credentials, cookies, or prior interaction required.

Tested on: PHP 8.1.34, macOS, fresh clone with no configuration applied.
Proof of concept screenshot/PDF available.

Vulnerability type: Unauthenticated Information Disclosure (CWE-200)

Any unauthenticated remote attacker who can reach a freshly deployed FacturaScripts instance before installation is completed can retrieve the full PHP environment. On production deployments this includes:

• Database credentials (DB_PASSWORD, DB_USER) if set as environment variables
• Application secrets (APP_KEY, JWT secrets) if set as environment variables
• Cloud provider credentials (AWS_SECRET_ACCESS_KEY, etc.) if present
• Full server filesystem paths enabling targeted path traversal attempts
• Exact PHP version and loaded extensions enabling version-specific attacks
• All HTTP headers revealing internal infrastructure details
• Database connection configuration (mysqli default socket, PDO drivers)
• Exact PHP version enabling version-specific CVE targeting (PHP 8.1.34)

Fresh deployments are commonly left unconfigured for extended periods on shared hosting and cloud environments, making this window reliably exploitable in real-world scenarios.

Fix: Remove lines 115-118 from Core/Controller/Installer.php:

if ('TRUE' === $this->request->query('phpinfo', '')) {
    phpinfo();
    return;
}

CVE-2026-42878 has a CVSS score of 5.3 (Medium). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. No fixed version is listed yet, so configuration controls and monitoring matter more in the interim.

Kodem intelligence

1. What is CVE-2026-42878? CVE-2026-42878 is a medium-severity security vulnerability in facturascripts/facturascripts (composer), affecting versions >= 2026, <= 2026.1. No fixed version is listed yet.
2. How severe is CVE-2026-42878? CVE-2026-42878 has a CVSS score of 5.3 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of facturascripts/facturascripts are affected by CVE-2026-42878? facturascripts/facturascripts (composer) versions >= 2026, <= 2026.1 is affected.
4. Is there a fix for CVE-2026-42878? No fixed version is listed for CVE-2026-42878 yet. Monitor the advisory for updates and apply mitigations in the interim.
5. Is CVE-2026-42878 exploitable, and should I be worried? Whether CVE-2026-42878 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-42878 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.