File CVE-2024-41991.patch of Package python-Django.36738
From 772a73f70c3d249c99c23012849e66276b7b0715 Mon Sep 17 00:00:00 2001
From: Mariusz Felisiak <felisiak.mariusz@gmail.com>
Date: Wed, 10 Jul 2024 20:30:12 +0200
Subject: [PATCH 3/4] [4.2.x] Fixed CVE-2024-41991 -- Prevented potential ReDoS
in django.utils.html.urlize() and AdminURLFieldWidget.
Thanks Seokchan Yoon for the report.
Co-authored-by: Sarah Boyce <42296566+sarahboyce@users.noreply.github.com>
---
django/contrib/admin/widgets.py | 2 +-
django/utils/html.py | 10 ++++++++--
tests/admin_widgets/tests.py | 7 ++++++-
tests/utils_tests/test_html.py | 13 +++++++++++++
5 files changed, 35 insertions(+), 4 deletions(-)
diff --git a/django/contrib/admin/widgets.py b/django/contrib/admin/widgets.py
index 5e3416bc28..3d11a40efe 100644
--- a/django/contrib/admin/widgets.py
+++ b/django/contrib/admin/widgets.py
@@ -383,7 +383,7 @@ class AdminURLFieldWidget(forms.URLInput):
context["current_label"] = _("Currently:")
context["change_label"] = _("Change:")
context["widget"]["href"] = (
- smart_urlquote(context["widget"]["value"]) if value else ""
+ smart_urlquote(context["widget"]["value"]) if url_valid else ""
)
context["url_valid"] = url_valid
return context
diff --git a/django/utils/html.py b/django/utils/html.py
index dd52f1f7fe..23575d3c11 100644
--- a/django/utils/html.py
+++ b/django/utils/html.py
@@ -13,6 +13,8 @@ from django.utils.regex_helper import _lazy_re_compile
from django.utils.safestring import SafeData, SafeString, mark_safe
from django.utils.text import normalize_newlines
+MAX_URL_LENGTH = 2048
+
@keep_lazy(SafeString)
def escape(text):
@@ -300,9 +302,9 @@ class Urlizer:
# Make URL we want to point to.
url = None
nofollow_attr = ' rel="nofollow"' if nofollow else ""
- if self.simple_url_re.match(middle):
+ if len(middle) <= MAX_URL_LENGTH and self.simple_url_re.match(middle):
url = smart_urlquote(html.unescape(middle))
- elif self.simple_url_2_re.match(middle):
+ elif len(middle) <= MAX_URL_LENGTH and self.simple_url_2_re.match(middle):
url = smart_urlquote("http://%s" % html.unescape(middle))
elif ":" not in middle and self.is_email_simple(middle):
local, domain = middle.rsplit("@", 1)
@@ -417,6 +419,10 @@ class Urlizer:
except ValueError:
# value contains more than one @.
return False
+ # Max length for domain name labels is 63 characters per RFC 1034.
+ # Helps to avoid ReDoS vectors in the domain part.
+ if len(p2) > 63:
+ return False
# Dot must be in p2 (e.g. example.com)
if "." not in p2 or p2.startswith("."):
return False
diff --git a/tests/admin_widgets/tests.py b/tests/admin_widgets/tests.py
index 0e20206048..4281ed07c6 100644
--- a/tests/admin_widgets/tests.py
+++ b/tests/admin_widgets/tests.py
@@ -461,7 +461,12 @@ class AdminSplitDateTimeWidgetTest(SimpleTestCase):
class AdminURLWidgetTest(SimpleTestCase):
def test_get_context_validates_url(self):
w = widgets.AdminURLFieldWidget()
- for invalid in ["", "/not/a/full/url/", 'javascript:alert("Danger XSS!")']:
+ for invalid in [
+ "",
+ "/not/a/full/url/",
+ 'javascript:alert("Danger XSS!")',
+ "http://" + "한.글." * 1_000_000 + "com",
+ ]:
with self.subTest(url=invalid):
self.assertFalse(w.get_context("name", invalid, {})["url_valid"])
self.assertTrue(w.get_context("name", "http://example.com", {})["url_valid"])
diff --git a/tests/utils_tests/test_html.py b/tests/utils_tests/test_html.py
index c45e0dfac1..83ebe4334b 100644
--- a/tests/utils_tests/test_html.py
+++ b/tests/utils_tests/test_html.py
@@ -328,6 +328,15 @@ class TestUtilsHtml(SimpleTestCase):
'Search for <a href="http://google.com/?q=">google.com/?q=</a>!',
),
("foo@example.com", '<a href="mailto:foo@example.com">foo@example.com</a>'),
+ (
+ "test@" + "한.글." * 15 + "aaa",
+ '<a href="mailto:test@'
+ + "xn--6q8b.xn--bj0b." * 15
+ + 'aaa">'
+ + "test@"
+ + "한.글." * 15
+ + "aaa</a>",
+ ),
)
for value, output in tests:
with self.subTest(value=value):
@@ -336,6 +345,10 @@ class TestUtilsHtml(SimpleTestCase):
def test_urlize_unchanged_inputs(self):
tests = (
("a" + "@a" * 50000) + "a", # simple_email_re catastrophic test
+ # Unicode domain catastrophic tests.
+ "a@" + "한.글." * 1_000_000 + "a",
+ "http://" + "한.글." * 1_000_000 + "com",
+ "www." + "한.글." * 1_000_000 + "com",
("a" + "." * 1000000) + "a", # trailing_punctuation catastrophic test
"foo@",
"@foo.com",
--
2.34.1
