diff --git a/system/HTTP/UserAgent.php b/system/HTTP/UserAgent.php
index 5e8eece63659..ba9e544ae2f8 100644
--- a/system/HTTP/UserAgent.php
+++ b/system/HTTP/UserAgent.php
@@ -109,8 +109,10 @@ public function __construct(?UserAgents $config = null)
     {
         $this->config = $config ?? config(UserAgents::class);
 
-        if (isset($_SERVER['HTTP_USER_AGENT'])) {
-            $this->agent = trim($_SERVER['HTTP_USER_AGENT']);
+        $userAgent = service('superglobals')->server('HTTP_USER_AGENT');
+
+        if ($userAgent !== null) {
+            $this->agent = trim($userAgent);
             $this->compileData();
         }
     }
@@ -175,10 +177,11 @@ public function isMobile(?string $key = null): bool
     public function isReferral(): bool
     {
         if (! isset($this->referrer)) {
-            if (empty($_SERVER['HTTP_REFERER'])) {
+            $referer = service('superglobals')->server('HTTP_REFERER');
+            if ($referer === null || $referer === '') {
                 $this->referrer = false;
             } else {
-                $refererHost = @parse_url($_SERVER['HTTP_REFERER'], PHP_URL_HOST);
+                $refererHost = @parse_url($referer, PHP_URL_HOST);
                 $ownHost     = parse_url(\base_url(), PHP_URL_HOST);
 
                 $this->referrer = ($refererHost && $refererHost !== $ownHost);
@@ -241,7 +244,9 @@ public function getMobile(): string
      */
     public function getReferrer(): string
     {
-        return empty($_SERVER['HTTP_REFERER']) ? '' : trim($_SERVER['HTTP_REFERER']);
+        $referrer = service('superglobals')->server('HTTP_REFERER');
+
+        return $referrer === null ? '' : trim($referrer);
     }
 
     /**
diff --git a/tests/system/HTTP/IncomingRequestTest.php b/tests/system/HTTP/IncomingRequestTest.php
index 1240d0885b23..c6a693b7681c 100644
--- a/tests/system/HTTP/IncomingRequestTest.php
+++ b/tests/system/HTTP/IncomingRequestTest.php
@@ -760,7 +760,7 @@ public function testIsSecureForwarded(): void
 
     public function testUserAgent(): void
     {
-        $_SERVER['HTTP_USER_AGENT'] = 'Mozilla';
+        service('superglobals')->setServer('HTTP_USER_AGENT', 'Mozilla');
 
         $config  = new App();
         $request = $this->createRequest($config);
diff --git a/tests/system/HTTP/UserAgentTest.php b/tests/system/HTTP/UserAgentTest.php
index 9799a79c2851..c43c46354e87 100644
--- a/tests/system/HTTP/UserAgentTest.php
+++ b/tests/system/HTTP/UserAgentTest.php
@@ -31,7 +31,7 @@ protected function setUp(): void
         parent::setUp();
 
         // set a baseline user agent
-        $_SERVER['HTTP_USER_AGENT'] = $this->_user_agent;
+        service('superglobals')->setServer('HTTP_USER_AGENT', $this->_user_agent);
 
         $this->agent = new UserAgent();
     }
@@ -39,9 +39,8 @@ protected function setUp(): void
     public function testMobile(): void
     {
         // Mobile Not Set
-        $_SERVER['HTTP_USER_AGENT'] = $this->_mobile_ua;
+        service('superglobals')->setServer('HTTP_USER_AGENT', $this->_mobile_ua);
         $this->assertFalse($this->agent->isMobile());
-        unset($_SERVER['HTTP_USER_AGENT']);
     }
 
     public function testIsFunctions(): void
@@ -55,12 +54,13 @@ public function testIsFunctions(): void
 
     public function testReferrer(): void
     {
-        $_SERVER['HTTP_REFERER'] = 'http://codeigniter.com/user_guide/';
+        service('superglobals')->setServer('HTTP_REFERER', 'http://codeigniter.com/user_guide/');
+
         $this->assertTrue($this->agent->isReferral());
         $this->assertSame('http://codeigniter.com/user_guide/', $this->agent->getReferrer());
 
         $this->setPrivateProperty($this->agent, 'referrer', null);
-        unset($_SERVER['HTTP_REFERER']);
+        service('superglobals')->setServer('HTTP_REFERER', '');
         $this->assertFalse($this->agent->isReferral());
         $this->assertSame('', $this->agent->getReferrer());
     }
@@ -108,7 +108,7 @@ public function testParseBot(): void
 
     public function testEmptyUserAgentVariable(): void
     {
-        unset($_SERVER['HTTP_USER_AGENT']);
+        service('superglobals')->setServer('HTTP_USER_AGENT', '');
         $agent = new UserAgent();
         $this->assertEmpty((string) $agent);
     }
diff --git a/utils/phpstan-baseline/codeigniter.superglobalAccess.neon b/utils/phpstan-baseline/codeigniter.superglobalAccess.neon
index 05153d87fb35..00869afc1f4e 100644
--- a/utils/phpstan-baseline/codeigniter.superglobalAccess.neon
+++ b/utils/phpstan-baseline/codeigniter.superglobalAccess.neon
@@ -1,4 +1,4 @@
-# total 77 errors
+# total 68 errors
 
 parameters:
     ignoreErrors:
@@ -117,16 +117,6 @@ parameters:
             count: 2
             path: ../../system/HTTP/Response.php
 
-        -
-            message: '#^Accessing offset ''HTTP_REFERER'' directly on \$_SERVER is discouraged\.$#'
-            count: 4
-            path: ../../system/HTTP/UserAgent.php
-
-        -
-            message: '#^Accessing offset ''HTTP_USER_AGENT'' directly on \$_SERVER is discouraged\.$#'
-            count: 2
-            path: ../../system/HTTP/UserAgent.php
-
         -
             message: '#^Accessing offset mixed directly on \$_GET is discouraged\.$#'
             count: 1
@@ -212,16 +202,6 @@ parameters:
             count: 1
             path: ../../tests/system/HTTP/SiteURIFactoryDetectRoutePathTest.php
 
-        -
-            message: '#^Accessing offset ''HTTP_REFERER'' directly on \$_SERVER is discouraged\.$#'
-            count: 1
-            path: ../../tests/system/HTTP/UserAgentTest.php
-
-        -
-            message: '#^Accessing offset ''HTTP_USER_AGENT'' directly on \$_SERVER is discouraged\.$#'
-            count: 2
-            path: ../../tests/system/HTTP/UserAgentTest.php
-
         -
             message: '#^Accessing offset ''HTTP_HOST'' directly on \$_SERVER is discouraged\.$#'
             count: 1
diff --git a/utils/phpstan-baseline/codeigniter.superglobalAccessAssign.neon b/utils/phpstan-baseline/codeigniter.superglobalAccessAssign.neon
index 4a3113467afe..6a5f6dccbf23 100644
--- a/utils/phpstan-baseline/codeigniter.superglobalAccessAssign.neon
+++ b/utils/phpstan-baseline/codeigniter.superglobalAccessAssign.neon
@@ -1,4 +1,4 @@
-# total 463 errors
+# total 459 errors
 
 parameters:
     ignoreErrors:
@@ -337,11 +337,6 @@ parameters:
             count: 2
             path: ../../tests/system/HTTP/IncomingRequestTest.php
 
-        -
-            message: '#^Assigning ''Mozilla'' directly on offset ''HTTP_USER_AGENT'' of \$_SERVER is discouraged\.$#'
-            count: 1
-            path: ../../tests/system/HTTP/IncomingRequestTest.php
-
         -
             message: '#^Assigning ''fr\-FR; q\=1\.0, en; q\=0\.5'' directly on offset ''HTTP_ACCEPT_LANGUAGE'' of \$_SERVER is discouraged\.$#'
             count: 1
@@ -662,16 +657,6 @@ parameters:
             count: 3
             path: ../../tests/system/HTTP/URITest.php
 
-        -
-            message: '#^Assigning ''http\://codeigniter\.com/user_guide/'' directly on offset ''HTTP_REFERER'' of \$_SERVER is discouraged\.$#'
-            count: 1
-            path: ../../tests/system/HTTP/UserAgentTest.php
-
-        -
-            message: '#^Assigning string directly on offset ''HTTP_USER_AGENT'' of \$_SERVER is discouraged\.$#'
-            count: 2
-            path: ../../tests/system/HTTP/UserAgentTest.php
-
         -
             message: '#^Assigning ''/'' directly on offset ''REQUEST_URI'' of \$_SERVER is discouraged\.$#'
             count: 1
diff --git a/utils/phpstan-baseline/empty.notAllowed.neon b/utils/phpstan-baseline/empty.notAllowed.neon
index 9bdf7e5f5720..faf902d5ec10 100644
--- a/utils/phpstan-baseline/empty.notAllowed.neon
+++ b/utils/phpstan-baseline/empty.notAllowed.neon
@@ -1,4 +1,4 @@
-# total 239 errors
+# total 237 errors
 
 parameters:
     ignoreErrors:
@@ -242,11 +242,6 @@ parameters:
             count: 2
             path: ../../system/HTTP/Response.php
 
-        -
-            message: '#^Construct empty\(\) is not allowed\. Use more strict comparison\.$#'
-            count: 2
-            path: ../../system/HTTP/UserAgent.php
-
         -
             message: '#^Construct empty\(\) is not allowed\. Use more strict comparison\.$#'
             count: 1
diff --git a/utils/phpstan-baseline/loader.neon b/utils/phpstan-baseline/loader.neon
index e155430838ce..b37223d367be 100644
--- a/utils/phpstan-baseline/loader.neon
+++ b/utils/phpstan-baseline/loader.neon
@@ -1,4 +1,4 @@
-# total 2788 errors
+# total 2773 errors
 
 includes:
     - argument.type.neon