diff --git modules/update/update.manager.inc modules/update/update.manager.inc
index 11a3c8e..1ecf3dd 100644
--- modules/update/update.manager.inc
+++ modules/update/update.manager.inc
@@ -498,6 +498,12 @@ function update_manager_install_form_validate($form, &$form_state) {
   if (!($form_state['values']['project_url'] XOR !empty($_FILES['files']['name']['project_upload']))) {
     form_set_error('project_url', t('You must either provide a URL or upload an archive file to install.'));
   }
+
+  if ($form_state['values']['project_url']) {
+    if (!valid_url($form_state['values']['project_url'], TRUE)) {
+      form_set_error('project_url', t('The provided URL is invalid.'));
+    }
+  }
 }
 
 /**
diff --git sites/default/default.settings.php sites/default/default.settings.php
old mode 100644
new mode 100755