Fix XSS reported on Security list

No CVE-ID yet

August 18, 2015
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Reported to Quantopian by Juan Broullón <[e-mail]>...

If you create a new folder in the iPython file browser and set
Javascript code as its name the code injected will be executed. So, if I
create a folder called "><img src=x onerror=alert(document.cookie)> and
then I access to it, the cookies will be prompted.

The XSS code is also executed if you access a link pointing directly at
the folder.

  jik
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IPython/html/notebookapp.py

@@ -158,7 +158,9 b' class NotebookWebApplication(web.Application):'
             _template_path = (_template_path,)
         template_path = [os.path.expanduser(path) for path in _template_path]
 
-        jenv_opt = jinja_env_options if jinja_env_options else {}
+        jenv_opt = {"autoescape": True}
+        jenv_opt.update(jinja_env_options if jinja_env_options else {})
+
         env = Environment(loader=FileSystemLoader(template_path), **jenv_opt)
         
         sys_info = get_sys_info()