diff --git a/core/src/main/java/org/elasticsearch/common/settings/AddStringKeyStoreCommand.java b/core/src/main/java/org/elasticsearch/common/settings/AddStringKeyStoreCommand.java
index 7ac78c15b9a..1074f2ac552 100644
--- a/core/src/main/java/org/elasticsearch/common/settings/AddStringKeyStoreCommand.java
+++ b/core/src/main/java/org/elasticsearch/common/settings/AddStringKeyStoreCommand.java
@@ -64,6 +64,9 @@ class AddStringKeyStoreCommand extends EnvironmentAwareCommand {
         keystore.decrypt(new char[0] /* TODO: prompt for password when they are supported */);
 
         String setting = arguments.value(options);
+        if (setting == null) {
+            throw new UserException(ExitCodes.DATA_ERROR, "the setting name can not be null.");
+        }
         if (keystore.getSettings().contains(setting) && options.has(forceOption) == false) {
             if (terminal.promptYesNo("Setting " + setting + " already exists. Overwrite?", false) == false) {
                 terminal.println("Exiting without modifying keystore.");