diff --git a/system/Session/Session.php b/system/Session/Session.php
index ff40a4714e38..3b7dff2d6243 100644
--- a/system/Session/Session.php
+++ b/system/Session/Session.php
@@ -503,7 +503,7 @@ public function get(string $key = null)
 		}
 		elseif (empty($_SESSION))
 		{
-			return [];
+			return $key === null ? [] : null;
 		}
 
 		if (! empty($key))
diff --git a/tests/system/Session/SessionTest.php b/tests/system/Session/SessionTest.php
index d22819f469a3..9027088b9ec6 100644
--- a/tests/system/Session/SessionTest.php
+++ b/tests/system/Session/SessionTest.php
@@ -129,6 +129,28 @@ public function testGetReturnsNullWhenNotFound()
 		$this->assertNull($session->get('foo'));
 	}
 
+	public function testGetReturnsNullWhenNotFoundWithXmlHttpRequest()
+	{
+		$_SERVER['HTTP_X_REQUESTED_WITH'] = 'xmlhttprequest';
+		$_SESSION                         = [];
+
+		$session = $this->getInstance();
+		$session->start();
+
+		$this->assertNull($session->get('foo'));
+	}
+
+	public function testGetReturnsEmptyArrayWhenWithXmlHttpRequest()
+	{
+		$_SERVER['HTTP_X_REQUESTED_WITH'] = 'xmlhttprequest';
+		$_SESSION                         = [];
+
+		$session = $this->getInstance();
+		$session->start();
+
+		$this->assertEquals([], $session->get());
+	}
+
 	public function testGetReturnsItemValueisZero()
 	{
 		$_SESSION = [];