diff --git a/src/Symfony/Component/Security/Core/Authentication/Token/UsernamePasswordToken.php b/src/Symfony/Component/Security/Core/Authentication/Token/UsernamePasswordToken.php
index bf35c98d5580f..fb1c2b33bb1e7 100644
--- a/src/Symfony/Component/Security/Core/Authentication/Token/UsernamePasswordToken.php
+++ b/src/Symfony/Component/Security/Core/Authentication/Token/UsernamePasswordToken.php
@@ -99,6 +99,7 @@ public function __serialize(): array
     public function __unserialize(array $data): void
     {
         [$this->credentials, $this->providerKey, $parentData] = $data;
+        $parentData = \is_array($parentData) ? $parentData : unserialize($parentData);
         parent::__unserialize($parentData);
     }
 }