diff --git a/lib/ole/ranges_io.rb b/lib/ole/ranges_io.rb
index 20918ed..50cf1df 100644
--- a/lib/ole/ranges_io.rb
+++ b/lib/ole/ranges_io.rb
@@ -156,7 +156,7 @@ def eof?
 
 	# read bytes from file, to a maximum of +limit+, or all available if unspecified.
 	def read limit=nil
-		data = ''
+		data = ''.dup
 		return data if eof?
 		limit ||= size
 		pos, len = @ranges[@active]