diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/AssetsInstallCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/AssetsInstallCommand.php
index b81e0be294f88..c3e1456b3863d 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/AssetsInstallCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/AssetsInstallCommand.php
@@ -99,8 +99,7 @@ protected function execute(InputInterface $input, OutputInterface $output): int
     {
         /** @var KernelInterface $kernel */
         $kernel = $this->getApplication()->getKernel();
-        $targetArg = rtrim($input->getArgument('target'), '/');
-
+        $targetArg = rtrim($input->getArgument('target') ?? '', '/');
         if (!$targetArg) {
             $targetArg = $this->getPublicDirectory($kernel->getContainer());
         }