diff --git a/src/Symfony/Bridge/Monolog/Handler/ElasticsearchLogstashHandler.php b/src/Symfony/Bridge/Monolog/Handler/ElasticsearchLogstashHandler.php
index 612350200e3d6..c31dba880295c 100644
--- a/src/Symfony/Bridge/Monolog/Handler/ElasticsearchLogstashHandler.php
+++ b/src/Symfony/Bridge/Monolog/Handler/ElasticsearchLogstashHandler.php
@@ -129,6 +129,16 @@ private function sendToElasticsearch(array $records)
         $this->wait(false);
     }
 
+    public function __sleep()
+    {
+        throw new \BadMethodCallException('Cannot serialize '.__CLASS__);
+    }
+
+    public function __wakeup()
+    {
+        throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+    }
+
     public function __destruct()
     {
         $this->wait(true);
diff --git a/src/Symfony/Component/ErrorHandler/BufferingLogger.php b/src/Symfony/Component/ErrorHandler/BufferingLogger.php
index 16e433dedf898..72be64d1278a4 100644
--- a/src/Symfony/Component/ErrorHandler/BufferingLogger.php
+++ b/src/Symfony/Component/ErrorHandler/BufferingLogger.php
@@ -35,6 +35,16 @@ public function cleanLogs(): array
         return $logs;
     }
 
+    public function __sleep()
+    {
+        throw new \BadMethodCallException('Cannot serialize '.__CLASS__);
+    }
+
+    public function __wakeup()
+    {
+        throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+    }
+
     public function __destruct()
     {
         foreach ($this->logs as [$level, $message, $context]) {
diff --git a/src/Symfony/Component/HttpClient/Chunk/ErrorChunk.php b/src/Symfony/Component/HttpClient/Chunk/ErrorChunk.php
index c3df62ce32695..5e2ba0a6971b1 100644
--- a/src/Symfony/Component/HttpClient/Chunk/ErrorChunk.php
+++ b/src/Symfony/Component/HttpClient/Chunk/ErrorChunk.php
@@ -115,6 +115,16 @@ public function didThrow(): bool
         return $this->didThrow;
     }
 
+    public function __sleep()
+    {
+        throw new \BadMethodCallException('Cannot serialize '.__CLASS__);
+    }
+
+    public function __wakeup()
+    {
+        throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+    }
+
     public function __destruct()
     {
         if (!$this->didThrow) {
diff --git a/src/Symfony/Component/HttpClient/CurlHttpClient.php b/src/Symfony/Component/HttpClient/CurlHttpClient.php
index e69761b392ffa..766cf222c2b6f 100644
--- a/src/Symfony/Component/HttpClient/CurlHttpClient.php
+++ b/src/Symfony/Component/HttpClient/CurlHttpClient.php
@@ -362,6 +362,16 @@ public function reset()
         }
     }
 
+    public function __sleep()
+    {
+        throw new \BadMethodCallException('Cannot serialize '.__CLASS__);
+    }
+
+    public function __wakeup()
+    {
+        throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+    }
+
     public function __destruct()
     {
         $this->reset();
diff --git a/src/Symfony/Component/HttpClient/HttplugClient.php b/src/Symfony/Component/HttpClient/HttplugClient.php
index 5d691e024d47c..a825c5d078f05 100644
--- a/src/Symfony/Component/HttpClient/HttplugClient.php
+++ b/src/Symfony/Component/HttpClient/HttplugClient.php
@@ -218,6 +218,16 @@ public function createUri($uri): UriInterface
         throw new \LogicException(sprintf('You cannot use "%s()" as the "nyholm/psr7" package is not installed. Try running "composer require nyholm/psr7".', __METHOD__));
     }
 
+    public function __sleep()
+    {
+        throw new \BadMethodCallException('Cannot serialize '.__CLASS__);
+    }
+
+    public function __wakeup()
+    {
+        throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+    }
+
     public function __destruct()
     {
         $this->wait();
diff --git a/src/Symfony/Component/HttpClient/Response/ResponseTrait.php b/src/Symfony/Component/HttpClient/Response/ResponseTrait.php
index d6ddae6def910..69caabf4b85d0 100644
--- a/src/Symfony/Component/HttpClient/Response/ResponseTrait.php
+++ b/src/Symfony/Component/HttpClient/Response/ResponseTrait.php
@@ -199,6 +199,16 @@ public function toStream(bool $throw = true)
         return $stream;
     }
 
+    public function __sleep()
+    {
+        throw new \BadMethodCallException('Cannot serialize '.__CLASS__);
+    }
+
+    public function __wakeup()
+    {
+        throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+    }
+
     /**
      * Closes the response and all its network handles.
      */
diff --git a/src/Symfony/Component/Mailer/Transport/Smtp/SmtpTransport.php b/src/Symfony/Component/Mailer/Transport/Smtp/SmtpTransport.php
index 5ef8a8825509f..c924b5e93b6d9 100644
--- a/src/Symfony/Component/Mailer/Transport/Smtp/SmtpTransport.php
+++ b/src/Symfony/Component/Mailer/Transport/Smtp/SmtpTransport.php
@@ -331,6 +331,16 @@ private function checkRestartThreshold(): void
         $this->restartCounter = 0;
     }
 
+    public function __sleep()
+    {
+        throw new \BadMethodCallException('Cannot serialize '.__CLASS__);
+    }
+
+    public function __wakeup()
+    {
+        throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+    }
+
     public function __destruct()
     {
         $this->stop();
diff --git a/src/Symfony/Component/Mime/Part/DataPart.php b/src/Symfony/Component/Mime/Part/DataPart.php
index 213f3c10c8826..0da9230c29a8d 100644
--- a/src/Symfony/Component/Mime/Part/DataPart.php
+++ b/src/Symfony/Component/Mime/Part/DataPart.php
@@ -155,7 +155,13 @@ public function __wakeup()
         $r->setValue($this, $this->_headers);
         unset($this->_headers);
 
+        if (!\is_array($this->_parent)) {
+            throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+        }
         foreach (['body', 'charset', 'subtype', 'disposition', 'name', 'encoding'] as $name) {
+            if (null !== $this->_parent[$name] && !\is_string($this->_parent[$name])) {
+                throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
+            }
             $r = new \ReflectionProperty(TextPart::class, $name);
             $r->setAccessible(true);
             $r->setValue($this, $this->_parent[$name]);