diff --git a/src/Symfony/Component/HttpKernel/Kernel.php b/src/Symfony/Component/HttpKernel/Kernel.php
index 9fc6b36fc52bc..c31a4b7ca33f2 100644
--- a/src/Symfony/Component/HttpKernel/Kernel.php
+++ b/src/Symfony/Component/HttpKernel/Kernel.php
@@ -778,7 +778,9 @@ private function preBoot(): ContainerInterface
             $this->startTime = microtime(true);
         }
         if ($this->debug && !isset($_ENV['SHELL_VERBOSITY']) && !isset($_SERVER['SHELL_VERBOSITY'])) {
-            putenv('SHELL_VERBOSITY=3');
+            if (\function_exists('putenv')) {
+                putenv('SHELL_VERBOSITY=3');
+            }
             $_ENV['SHELL_VERBOSITY'] = 3;
             $_SERVER['SHELL_VERBOSITY'] = 3;
         }