--- a/testing/geckodriver/src/marionette.rs
+++ b/testing/geckodriver/src/marionette.rs
@@ -49,17 +49,19 @@ use webdriver::common::{Date, ELEMENT_KE
 use webdriver::error::{ErrorStatus, WebDriverError, WebDriverResult};
 use webdriver::server::{WebDriverHandler, Session};
 use webdriver::httpapi::{WebDriverExtensionRoute};
 
 use capabilities::{FirefoxCapabilities, FirefoxOptions};
 use logging;
 use prefs;
 
-const DEFAULT_HOST: &'static str = "localhost";
+// Bind host to IPv4 only because Marionette only listens on that interface
+const DEFAULT_HOST: &'static str = "127.0.0.1";
+
 const CHROME_ELEMENT_KEY: &'static str = "chromeelement-9fc5-4b51-a3c8-01716eedeb04";
 const LEGACY_ELEMENT_KEY: &'static str = "ELEMENT";
 
 pub fn extension_routes() -> Vec<(Method, &'static str, GeckoExtensionRoute)> {
     return vec![(Method::Get, "/session/{sessionId}/moz/context", GeckoExtensionRoute::GetContext),
              (Method::Post, "/session/{sessionId}/moz/context", GeckoExtensionRoute::SetContext),
              (Method::Post,
               "/session/{sessionId}/moz/xbl/{elementId}/anonymous_children",