diff --git a/lib/filey-diff/data-sources/aws_sdk_s3.rb b/lib/filey-diff/data-sources/aws_sdk_s3.rb
index eaab3bf..0f1ad5e 100644
--- a/lib/filey-diff/data-sources/aws_sdk_s3.rb
+++ b/lib/filey-diff/data-sources/aws_sdk_s3.rb
@@ -86,6 +86,7 @@ def last_modified_and_md5_from_gzipped(s3_object, path)
           [s3_object.last_modified, md5]
         else
           tempfile = Tempfile.new(File.basename(path))
+          tempfile.binmode
           tempfile.write s3_object_contents
           tempfile.close