diff --git a/src/calibre/__init__.py b/src/calibre/__init__.py
index 360947de2a..3c61de4bec 100644
--- a/src/calibre/__init__.py
+++ b/src/calibre/__init__.py
@@ -69,7 +69,7 @@ def sanitize_file_name(name, substitute='_', as_unicode=False):
     one = re.sub(r'^\.+$', '_', one)
     if as_unicode:
         one = one.decode(filesystem_encoding)
-    return one
+    return one.replace('..', '_')
 
 
 class CommandLineError(Exception):