File CVE-2025-15282-urllib-ctrl-chars.patch of Package python310
From d6c6f0880dbc6ffd770b859087f4cd749a1d0dbb Mon Sep 17 00:00:00 2001
From: Seth Michael Larson <seth@python.org>
Date: Tue, 20 Jan 2026 14:45:58 -0600
Subject: [PATCH] [3.10] gh-143925: Reject control characters in data: URL
mediatypes (cherry picked from commit
f25509e78e8be6ea73c811ac2b8c928c28841b9f) (cherry picked from commit
2c9c746077d8119b5bcf5142316992e464594946)
Co-authored-by: Seth Michael Larson <seth@python.org>
---
Lib/test/test_urllib.py | 8 ++++++++
Lib/urllib/request.py | 5 +++++
Misc/NEWS.d/next/Security/2026-01-16-11-51-19.gh-issue-143925.mrtcHW.rst | 1 +
3 files changed, 14 insertions(+)
create mode 100644 Misc/NEWS.d/next/Security/2026-01-16-11-51-19.gh-issue-143925.mrtcHW.rst
Index: Python-3.10.19/Lib/test/test_urllib.py
===================================================================
--- Python-3.10.19.orig/Lib/test/test_urllib.py 2026-02-12 01:05:56.127447144 +0100
+++ Python-3.10.19/Lib/test/test_urllib.py 2026-02-12 01:08:02.226352573 +0100
@@ -11,6 +11,7 @@
from test import support
from test.support import os_helper
from test.support import warnings_helper
+from test.support import control_characters_c0
import os
try:
import ssl
@@ -683,6 +684,13 @@
# missing padding character
self.assertRaises(ValueError,urllib.request.urlopen,'data:;base64,Cg=')
+ def test_invalid_mediatype(self):
+ for c0 in control_characters_c0():
+ self.assertRaises(ValueError,urllib.request.urlopen,
+ f'data:text/html;{c0},data')
+ for c0 in control_characters_c0():
+ self.assertRaises(ValueError,urllib.request.urlopen,
+ f'data:text/html{c0};base64,ZGF0YQ==')
class urlretrieve_FileTests(unittest.TestCase):
"""Test urllib.urlretrieve() on local files"""
Index: Python-3.10.19/Lib/urllib/request.py
===================================================================
--- Python-3.10.19.orig/Lib/urllib/request.py 2026-02-12 01:05:56.627830069 +0100
+++ Python-3.10.19/Lib/urllib/request.py 2026-02-12 01:08:02.226810828 +0100
@@ -1654,6 +1654,11 @@
scheme, data = url.split(":",1)
mediatype, data = data.split(",",1)
+ # Disallow control characters within mediatype.
+ if re.search(r"[\x00-\x1F\x7F]", mediatype):
+ raise ValueError(
+ "Control characters not allowed in data: mediatype")
+
# even base64 encoded data URLs might be quoted so unquote in any case:
data = unquote_to_bytes(data)
if mediatype.endswith(";base64"):
Index: Python-3.10.19/Misc/NEWS.d/next/Security/2026-01-16-11-51-19.gh-issue-143925.mrtcHW.rst
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ Python-3.10.19/Misc/NEWS.d/next/Security/2026-01-16-11-51-19.gh-issue-143925.mrtcHW.rst 2026-02-12 01:08:02.227192287 +0100
@@ -0,0 +1 @@
+Reject control characters in ``data:`` URL media types.
