diff --git a/typo3/sysext/core/Classes/Http/NormalizedParams.php b/typo3/sysext/core/Classes/Http/NormalizedParams.php
index f2911395aa8f2d69a591485297837a2db287fbc0..6cfd5ea7822cfdfd5aa1726f848bc115ec86f243 100644
--- a/typo3/sysext/core/Classes/Http/NormalizedParams.php
+++ b/typo3/sysext/core/Classes/Http/NormalizedParams.php
@@ -720,9 +720,9 @@ class NormalizedParams
             // Choose which IP in list to use
             $configuredReverseProxyHeaderMultiValue = trim($configuration['reverseProxyHeaderMultiValue'] ?? '');
             if (!empty($ip) && $configuredReverseProxyHeaderMultiValue === 'last') {
-                $ip = array_pop($ip);
+                $ip = (string)array_pop($ip);
             } elseif (!empty($ip) && $configuredReverseProxyHeaderMultiValue === 'first') {
-                $ip = array_shift($ip);
+                $ip = (string)array_shift($ip);
             } else {
                 $ip = '';
             }
diff --git a/typo3/sysext/core/Classes/Http/Response.php b/typo3/sysext/core/Classes/Http/Response.php
index f75e78552ee806f2a33cd175cfcf0c748cecc5bb..bc15bc2d708ae08884f2fb5c14fdc50073fd9c5d 100644
--- a/typo3/sysext/core/Classes/Http/Response.php
+++ b/typo3/sysext/core/Classes/Http/Response.php
@@ -119,7 +119,7 @@ class Response extends Message implements ResponseInterface
     /**
      * Constructor for generating new responses
      *
-     * @param StreamInterface|string $body
+     * @param StreamInterface|string|null $body
      * @param int $statusCode
      * @param array $headers
      * @param string $reasonPhrase
diff --git a/typo3/sysext/core/Classes/Http/ServerRequestFactory.php b/typo3/sysext/core/Classes/Http/ServerRequestFactory.php
index 8e4daf213d1472a589e83547a22e03da013118ce..80d70c61bbcc8e939dc12d227ba3c5585ccabadd 100644
--- a/typo3/sysext/core/Classes/Http/ServerRequestFactory.php
+++ b/typo3/sysext/core/Classes/Http/ServerRequestFactory.php
@@ -82,7 +82,7 @@ class ServerRequestFactory implements ServerRequestFactoryInterface
         }
         $parsedBody = GeneralUtility::_POST();
         if (empty($parsedBody) && in_array($method, ['PUT', 'PATCH', 'DELETE'])) {
-            parse_str(file_get_contents('php://input'), $parsedBody);
+            parse_str((string)file_get_contents('php://input'), $parsedBody);
         }
         if (!empty($parsedBody)) {
             $request = $request->withParsedBody($parsedBody);
diff --git a/typo3/sysext/core/Classes/Http/UploadedFile.php b/typo3/sysext/core/Classes/Http/UploadedFile.php
index cc076497f26b1f0972464a5f55110adecdb97f9c..8579fc5ce0e364cb8c9a2e0d29085c9d401a870d 100644
--- a/typo3/sysext/core/Classes/Http/UploadedFile.php
+++ b/typo3/sysext/core/Classes/Http/UploadedFile.php
@@ -134,7 +134,7 @@ class UploadedFile implements UploadedFileInterface
             return $this->stream;
         }
 
-        $this->stream = new Stream($this->file);
+        $this->stream = new Stream((string)$this->file);
         return $this->stream;
     }
 
diff --git a/typo3/sysext/core/Classes/Http/Uri.php b/typo3/sysext/core/Classes/Http/Uri.php
index 9e89965c910a264ad2f483cba67dfa5e9eeff1a5..16e6fd6cfe52e267b2e346eed2c7f25b65de099b 100644
--- a/typo3/sysext/core/Classes/Http/Uri.php
+++ b/typo3/sysext/core/Classes/Http/Uri.php
@@ -606,7 +606,7 @@ class Uri implements UriInterface
      *
      * @param string $scheme
      * @param string $host
-     * @param int $port
+     * @param int|null $port
      * @return bool
      */
     protected function isNonStandardPort($scheme, $host, $port)