Issue 17538: Document XML vulnerabilties
diff --git a/Doc/library/xml.etree.elementtree.rst b/Doc/library/xml.etree.elementtree.rst
index cf0c33f..dc9ebb9 100644
--- a/Doc/library/xml.etree.elementtree.rst
+++ b/Doc/library/xml.etree.elementtree.rst
@@ -13,6 +13,14 @@
hierarchical data structures in memory. The type can be described as a cross
between a list and a dictionary.
+
+.. warning::
+
+ The :mod:`xml.etree.ElementTree` module is not secure against
+ maliciously constructed data. If you need to parse untrusted or
+ unauthenticated data see :ref:`xml-vulnerabilities`.
+
+
Each element has a number of properties associated with it:
* a tag which is a string identifying what kind of data this element represents