diff --git a/Gruntfile.coffee b/Gruntfile.coffee
index 4a7752092..85908b5b8 100755
--- a/Gruntfile.coffee
+++ b/Gruntfile.coffee
@@ -210,6 +210,7 @@ module.exports = (grunt) ->
         src: 'testbuilds/crx<%= pkg.meta.suffix.noupdate %>/*'
         dest: '/'
         date: '<%= pkg.meta.date %>'
+        mode: parseInt('644', 8)
 
     clean:
       builds: 'builds'