diff --git a/src/Ratchet/Http/OriginCheck.php b/src/Ratchet/Http/OriginCheck.php
index 257c847b..a4ca8400 100644
--- a/src/Ratchet/Http/OriginCheck.php
+++ b/src/Ratchet/Http/OriginCheck.php
@@ -33,7 +33,7 @@ public function __construct(MessageComponentInterface $component, array $allowed
      */
     #[HackSupportForPHP8] public function onOpen(ConnectionInterface $conn, ?RequestInterface $request = null) { /*
     public function onOpen(ConnectionInterface $conn, RequestInterface $request = null) { /**/
-        $header = (string)$request->getHeader('Origin')[0];
+        $header = $request->getHeaderLine('Origin');
         $origin = parse_url($header, PHP_URL_HOST) ?: $header;
 
         if (!in_array($origin, $this->allowedOrigins)) {
diff --git a/tests/unit/Http/OriginCheckTest.php b/tests/unit/Http/OriginCheckTest.php
index 3f804a04..42321518 100644
--- a/tests/unit/Http/OriginCheckTest.php
+++ b/tests/unit/Http/OriginCheckTest.php
@@ -13,7 +13,7 @@ class OriginCheckTest extends AbstractMessageComponentTestCase {
      */
     public function setUpConnection() {
         $this->_reqStub = $this->getMockBuilder('Psr\Http\Message\RequestInterface')->getMock();
-        $this->_reqStub->expects($this->any())->method('getHeader')->will($this->returnValue(['localhost']));
+        $this->_reqStub->expects($this->any())->method('getHeaderLine')->with('Origin')->willReturn('localhost');
 
         parent::setUpConnection();
 
@@ -44,6 +44,24 @@ public function testCloseOnNonMatchingOrigin() {
         $this->_serv->onOpen($this->_conn, $this->_reqStub);
     }
 
+    public function testCloseOnMissingOrigin() {
+        $this->_serv->allowedOrigins = ['socketo.me'];
+        $this->_conn->expects($this->once())->method('close');
+
+        $this->_reqStub->expects($this->once())->method('getHeaderLine')->with('Origin')->willReturn('');
+
+        $this->_serv->onOpen($this->_conn, $this->_reqStub);
+    }
+
+    public function testCloseOnDuplicateOrigin() {
+        $this->_serv->allowedOrigins = ['socketo.me'];
+        $this->_conn->expects($this->once())->method('close');
+
+        $this->_reqStub->expects($this->once())->method('getHeaderLine')->with('Origin')->willReturn('http://socketo.me,https://socketo.me');
+
+        $this->_serv->onOpen($this->_conn, $this->_reqStub);
+    }
+
     public function testOnMessage() {
         $this->passthroughMessageTest('Hello World!');
     }