diff --git a/src/Core/Injector/InjectionCreator.php b/src/Core/Injector/InjectionCreator.php
index 3dc7448ab..44fe99a21 100644
--- a/src/Core/Injector/InjectionCreator.php
+++ b/src/Core/Injector/InjectionCreator.php
@@ -20,6 +20,8 @@ class InjectionCreator implements Factory
         }
 
         if (count($params)) {
+            // Remove named keys to ensure that PHP7 and PHP8 interpret these the same way
+            $params = array_values($params);
             return $reflector->newInstanceArgs($params);
         }
 
diff --git a/src/Security/PasswordEncryptor.php b/src/Security/PasswordEncryptor.php
index 6b2b0e695..8a94ddebd 100644
--- a/src/Security/PasswordEncryptor.php
+++ b/src/Security/PasswordEncryptor.php
@@ -56,7 +56,8 @@ abstract class PasswordEncryptor
             return new $class;
         }
 
-        $arguments = $encryptors[$algorithm];
+        // Don't treat array keys as argument names - keeps PHP 7 and PHP 8 operating similarly
+        $arguments = array_values($encryptors[$algorithm]);
         return($refClass->newInstanceArgs($arguments));
     }