SameSite may allow cross-site request forgery (CSRF) protection to be bypassed

@@ -23,7 +23,7 @@
     },
     "require-dev": {
         "codeigniter4/devkit": "^1.0",
-        "codeigniter4/framework": "^4.1",
+        "codeigniter4/framework": "^4.2.3",
         "mockery/mockery": "^1.0"
     },
     "provide": {

@@ -12,6 +12,12 @@
 
 These instructions assume that you have already [installed the CodeIgniter 4 app starter](https://codeigniter.com/user_guide/installation/installing_composer.html) as the basis for your new project, set up your `.env` file, and created a database that you can access via the Spark CLI script.
 
+> **Note**
+> CodeIgniter Shield requires Codeigniter v4.2.3 or later.
+
+> **Note**
+> You must set ``Config\Security::$csrfProtection`` to `'session'` (or set `security.csrfProtection = session` in your `.env` file) for security reasons, if you use Session Authenticator.
+
 Installation is done through [Composer](https://getcomposer.org). The example assumes you have it installed globally.
 If you have it installed as a phar, or othewise you will need to adjust the way you call composer itself.
 

@@ -35,7 +35,7 @@ access for a mobile application that you build.
 
 Usage of Shield requires the following:
 
-- A [CodeIgniter 4](https://github.com/codeigniter4/CodeIgniter4/)-based project
+- A [CodeIgniter 4.2.3+](https://github.com/codeigniter4/CodeIgniter4/) based project
 - [Composer](https://getcomposer.org/) for package management
 - PHP 7.4.3+
 

@@ -15,11 +15,14 @@
 use CodeIgniter\Shield\Entities\UserIdentity;
 use CodeIgniter\Shield\Exceptions\InvalidArgumentException;
 use CodeIgniter\Shield\Exceptions\LogicException;
+use CodeIgniter\Shield\Exceptions\SecurityException;
 use CodeIgniter\Shield\Models\LoginModel;
 use CodeIgniter\Shield\Models\RememberModel;
 use CodeIgniter\Shield\Models\UserIdentityModel;
 use CodeIgniter\Shield\Models\UserModel;
 use CodeIgniter\Shield\Result;
+use Config\Security;
+use Config\Services;
 use stdClass;
 
 class Session implements AuthenticatorInterface
@@ -72,6 +75,25 @@ public function __construct(UserModel $provider)
         $this->loginModel        = model(LoginModel::class);
         $this->rememberModel     = model(RememberModel::class);
         $this->userIdentityModel = model(UserIdentityModel::class);
+
+        $this->checkSecurityConfig();
+    }
+
+    /**
+     * Checks less secure Configuration.
+     */
+    private function checkSecurityConfig(): void
+    {
+        /** @var Security $securityConfig */
+        $securityConfig = config('Security');
+
+        if ($securityConfig->csrfProtection === 'cookie') {
+            throw new SecurityException(
+                'Config\Security::$csrfProtection is set to \'cookie\'.'
+                . ' Same-site attackers may bypass the CSRF protection.'
+                . ' Please set it to \'session\'.'
+            );
+        }
     }
 
     /**
@@ -567,7 +589,10 @@ public function startLogin(User $user): void
 
         // Regenerate the session ID to help protect against session fixation
         if (ENVIRONMENT !== 'testing') {
-            session()->regenerate();
+            session()->regenerate(true);
+
+            // Regenerate CSRF token even if `security.regenerate = false`.
+            Services::security()->generateHash();
         }
 
         // Let the session know we're logged in

@@ -0,0 +1,9 @@
+<?php
+
+namespace CodeIgniter\Shield\Exceptions;
+
+use RuntimeException;
+
+class SecurityException extends RuntimeException
+{
+}

@@ -30,7 +30,6 @@ protected function setUp(): void
         parent::setUp();
 
         helper('auth');
-        Factories::reset();
 
         // Add auth routes
         $routes = service('routes');

@@ -33,5 +33,10 @@ protected function setUp(): void
         $config          = config('Auth');
         $config->actions = ['login' => null, 'register' => null];
         Factories::injectMock('config', 'Auth', $config);
+
+        // Set Config\Security::$csrfProtection to 'session'
+        $config                 = config('Security');
+        $config->csrfProtection = 'session';
+        Factories::injectMock('config', 'Security', $config);
     }
 }