diff --git a/core/lib/Drupal/Core/Extension/ExtensionList.php b/core/lib/Drupal/Core/Extension/ExtensionList.php
--- a/core/lib/Drupal/Core/Extension/ExtensionList.php
+++ b/core/lib/Drupal/Core/Extension/ExtensionList.php
@@ -339,11 +339,14 @@
    *   If there is no extension with the supplied name.
    */
   public function getExtensionInfo($extension_name) {
-    $all_info = $this->getAllInstalledInfo();
-    if (isset($all_info[$extension_name])) {
-      return $all_info[$extension_name];
-    }
-    throw new UnknownExtensionException("The {$this->type} $extension_name does not exist or is not installed.");
+    if (!empty($extension_name)) {
+      $all_info = $this->getAllInstalledInfo();
+      if (isset($all_info[$extension_name])) {
+        return $all_info[$extension_name];
+      }
+      throw new UnknownExtensionException("The {$this->type} $extension_name does not exist or is not installed.");
+    }
+    return null;
   }
 
   /**