From: Gregory P. Smith <greg@krypto.org>
Date: Tue, 16 Mar 2021 04:37:58 +0000 (-0700)
Subject: [3.9] bpo-43285: Add a What's New entry for 3.9.3. (GH-24888)
X-Git-Tag: v3.9.3~37
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=d0312cece9ce89d783687ff6dddaae6495e19fcf;p=thirdparty%2FPython%2Fcpython.git

[3.9] bpo-43285: Add a What's New entry for 3.9.3. (GH-24888)

Covers the ftplib security fix.
---

diff --git a/Doc/whatsnew/3.9.rst b/Doc/whatsnew/3.9.rst
index 3086930569dc..4cb49406d6b7 100644
--- a/Doc/whatsnew/3.9.rst
+++ b/Doc/whatsnew/3.9.rst
@@ -1529,3 +1529,12 @@ separator key, with ``&`` as the default.  This change also affects
 functions internally. For more details, please see their respective
 documentation.
 (Contributed by Adam Goldschmidt, Senthil Kumaran and Ken Jin in :issue:`42967`.)
+
+Notable changes in Python 3.9.3
+===============================
+
+A security fix alters the :class:`ftplib.FTP` behavior to not trust the
+IPv4 address sent from the remote server when setting up a passive data
+channel.  We reuse the ftp server IP address instead.  For unusual code
+requiring the old behavior, set a ``trust_server_pasv_ipv4_address``
+attribute on your FTP instance to ``True``.  (See :issue:`43285`)