diff --git a/settings/Controller/SecuritySettingsController.php b/settings/Controller/SecuritySettingsController.php
index 44e07f25a0b2d9ea57469a4b3c242bc2519a5d92..d0d5743779982598d1e7e70f83250d91ad94c8d2 100644
--- a/settings/Controller/SecuritySettingsController.php
+++ b/settings/Controller/SecuritySettingsController.php
@@ -61,7 +61,7 @@ class SecuritySettingsController extends Controller {
 	 * @return array
 	 */
 	public function trustedDomains($newTrustedDomain) {
-		$trustedDomains = $this->config->getSystemValue('trusted_domains');
+		$trustedDomains = $this->config->getSystemValue('trusted_domains', []);
 		$trustedDomains[] = $newTrustedDomain;
 		$this->config->setSystemValue('trusted_domains', $trustedDomains);
 
diff --git a/tests/Settings/Controller/SecuritySettingsControllerTest.php b/tests/Settings/Controller/SecuritySettingsControllerTest.php
index 11b0edcae237de80c8aa5ff6f221d33e58abe071..302dc730fc435e49243eb2d795422f4a0437150f 100644
--- a/tests/Settings/Controller/SecuritySettingsControllerTest.php
+++ b/tests/Settings/Controller/SecuritySettingsControllerTest.php
@@ -57,8 +57,8 @@ class SecuritySettingsControllerTest extends \PHPUnit_Framework_TestCase {
 		$this->container['Config']
 			->expects($this->once())
 			->method('getSystemValue')
-			->with('trusted_domains')
-			->will($this->returnValue(''));
+			->with($this->equalTo('trusted_domains'), $this->equalTo([]))
+			->willReturn([]);
 
 		$response = $this->securitySettingsController->trustedDomains('newdomain.com');
 		$expectedResponse = array('status' => 'success');