fix: correct getHostname() fallback logic in Email class

system/Email/Email.php

@@ -2142,12 +2142,16 @@ protected function getSMTPData()
      */
     protected function getHostname()
     {
-        if (isset($_SERVER['SERVER_NAME'])) {
-            return $_SERVER['SERVER_NAME'];
+        $superglobals = service('superglobals');
+
+        $serverName = $superglobals->server('SERVER_NAME');
+        if (! in_array($serverName, [null, ''], true)) {
+            return $serverName;
         }
 
-        if (isset($_SERVER['SERVER_ADDR'])) {
-            return '[' . $_SERVER['SERVER_ADDR'] . ']';
+        $serverAddr = $superglobals->server('SERVER_ADDR');
+        if (! in_array($serverAddr, [null, ''], true)) {
+            return '[' . $serverAddr . ']';
         }
 
         $hostname = gethostname();

tests/system/Email/EmailTest.php

@@ -16,16 +16,20 @@
 use CodeIgniter\Events\Events;
 use CodeIgniter\Test\CIUnitTestCase;
 use CodeIgniter\Test\Mock\MockEmail;
+use CodeIgniter\Test\ReflectionHelper;
 use ErrorException;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\Group;
+use ReflectionException;
 
 /**
  * @internal
  */
 #[Group('Others')]
 final class EmailTest extends CIUnitTestCase
 {
+    use ReflectionHelper;
+
     public function testEmailValidation(): void
     {
         $config           = config('Email');
@@ -215,4 +219,51 @@ public function testSetAttachmentCIDBufferString(): void
             $email->archive['body'],
         );
     }
+
+    /**
+     * @throws ReflectionException
+     */
+    public function testGetHostnameUsesServerName(): void
+    {
+        $email = $this->createMockEmail();
+
+        $superglobals = service('superglobals');
+        $superglobals->setServer('SERVER_NAME', 'example.test');
+
+        $getHostname = self::getPrivateMethodInvoker($email, 'getHostname');
+
+        $this->assertSame('example.test', $getHostname());
+    }
+
+    /**
+     * @throws ReflectionException
+     */
+    public function testGetHostnameUsesServerAddr(): void
+    {
+        $email = $this->createMockEmail();
+
+        $superglobals = service('superglobals');
+        $superglobals->setServer('SERVER_NAME', '');
+        $superglobals->setServer('SERVER_ADDR', '192.168.1.10');
+
+        $getHostname = self::getPrivateMethodInvoker($email, 'getHostname');
+
+        $this->assertSame('[192.168.1.10]', $getHostname());
+    }
+
+    /**
+     * @throws ReflectionException
+     */
+    public function testGetHostnameFallsBackToGethostnameFunction(): void
+    {
+        $email = $this->createMockEmail();
+
+        $superglobals = service('superglobals');
+        $superglobals->setServer('SERVER_NAME', '');
+        $superglobals->setServer('SERVER_ADDR', '');
+
+        $getHostname = self::getPrivateMethodInvoker($email, 'getHostname');
+
+        $this->assertSame(gethostname(), $getHostname());
+    }
 }

user_guide_src/source/changelogs/v4.6.2.rst

@@ -37,6 +37,7 @@ Bugs Fixed
 
 - **Cache:** Fixed a bug where a corrupted or unreadable cache file could cause an unhandled exception in ``FileHandler::getItem()``.
 - **Database:** Fixed a bug where ``when()`` and ``whenNot()`` in ``ConditionalTrait`` incorrectly evaluated certain falsy values (such as ``[]``, ``0``, ``0.0``, and ``'0'``) as truthy, causing callbacks to be executed unexpectedly. These methods now cast the condition to a boolean using ``(bool)`` to ensure consistent behavior with PHP's native truthiness.
+- **Email:** Fixed a bug where ``Email::getHostname()`` failed to use ``$_SERVER['SERVER_ADDR']`` when ``$_SERVER['SERVER_NAME']`` was not set.
 - **Security:** Fixed a bug where the ``sanitize_filename()`` function from the Security helper would throw an error when used in CLI requests.
 - **Session:** Fixed a bug where using the ``DatabaseHandler`` with an unsupported database driver (such as ``SQLSRV``, ``OCI8``, or ``SQLite3``) did not throw an appropriate error.
 

utils/phpstan-baseline/codeigniter.superglobalAccess.neon

@@ -1,4 +1,4 @@
-# total 83 errors
+# total 79 errors
 
 parameters:
     ignoreErrors:
@@ -67,16 +67,6 @@ parameters:
             count: 1
             path: ../../system/Config/Services.php
 
-        -
-            message: '#^Accessing offset ''SERVER_ADDR'' directly on \$_SERVER is discouraged\.$#'
-            count: 2
-            path: ../../system/Email/Email.php
-
-        -
-            message: '#^Accessing offset ''SERVER_NAME'' directly on \$_SERVER is discouraged\.$#'
-            count: 2
-            path: ../../system/Email/Email.php
-
         -
             message: '#^Accessing offset ''HTTP_USER_AGENT'' directly on \$_SERVER is discouraged\.$#'
             count: 2

utils/phpstan-baseline/loader.neon

@@ -1,4 +1,4 @@
-# total 3149 errors
+# total 3145 errors
 includes:
     - argument.type.neon
     - assign.propertyType.neon