File CVE-2021-28658.patch of Package python-Django
commit a5698e3dad85e4c39553ca0ac41549bbdf3c5b30
Author: Johannes Grassler <johannes.grassler@suse.com>
Date: Thu Apr 1 17:20:58 2021 +0200
CVE-2021-28658/0001-2.2.x-Fixed-CVE-2021-28658-Fixed-potential-directory.patch backported to SUSE-1.11.29
diff --git a/django/http/multipartparser.py b/django/http/multipartparser.py
index 67d0fc48d50a..176f953b5cd3 100644
--- a/django/http/multipartparser.py
+++ b/django/http/multipartparser.py
@@ -9,6 +9,7 @@ from __future__ import unicode_literals
import base64
import binascii
import cgi
+import os
import sys
from django.conf import settings
@@ -183,7 +184,7 @@ class MultiPartParser(object):
file_name = disposition.get('filename')
if file_name:
file_name = force_text(file_name, encoding, errors='replace')
- file_name = self.IE_sanitize(unescape_entities(file_name))
+ file_name = self.sanitize_file_name(file_name)
if not file_name:
continue
@@ -275,9 +276,13 @@ class MultiPartParser(object):
file_obj)
break
- def IE_sanitize(self, filename):
- """Cleanup filename from Internet Explorer full paths."""
- return filename and filename[filename.rfind("\\") + 1:].strip()
+ def sanitize_file_name(self, file_name):
+ file_name = unescape_entities(file_name)
+ # Cleanup Windows-style path separators.
+ file_name = file_name[file_name.rfind('\\') + 1:].strip()
+ return os.path.basename(file_name)
+
+ IE_sanitize = sanitize_file_name
def _close_files(self):
# Free up all file handles.
diff --git a/tests/file_uploads/tests.py b/tests/file_uploads/tests.py
index d8d96438fc57..d08bc8016eda 100644
--- a/tests/file_uploads/tests.py
+++ b/tests/file_uploads/tests.py
@@ -25,6 +25,21 @@ UNICODE_FILENAME = 'test-0123456789_中文_Orléans.jpg'
MEDIA_ROOT = sys_tempfile.mkdtemp()
UPLOAD_TO = os.path.join(MEDIA_ROOT, 'test_upload')
+CANDIDATE_TRAVERSAL_FILE_NAMES = [
+ '/tmp/hax0rd.txt', # Absolute path, *nix-style.
+ 'C:\\Windows\\hax0rd.txt', # Absolute path, win-style.
+ 'C:/Windows/hax0rd.txt', # Absolute path, broken-style.
+ '\\tmp\\hax0rd.txt', # Absolute path, broken in a different way.
+ '/tmp\\hax0rd.txt', # Absolute path, broken by mixing.
+ 'subdir/hax0rd.txt', # Descendant path, *nix-style.
+ 'subdir\\hax0rd.txt', # Descendant path, win-style.
+ 'sub/dir\\hax0rd.txt', # Descendant path, mixed.
+ '../../hax0rd.txt', # Relative path, *nix-style.
+ '..\\..\\hax0rd.txt', # Relative path, win-style.
+ '../..\\hax0rd.txt', # Relative path, mixed.
+ '../hax0rd.txt', # HTML entities.
+]
+
@override_settings(MEDIA_ROOT=MEDIA_ROOT, ROOT_URLCONF='file_uploads.urls', MIDDLEWARE_CLASSES=())
class FileUploadTests(TestCase):
@@ -216,22 +231,8 @@ class FileUploadTests(TestCase):
# a malicious payload with an invalid file name (containing os.sep or
# os.pardir). This similar to what an attacker would need to do when
# trying such an attack.
- scary_file_names = [
- "/tmp/hax0rd.txt", # Absolute path, *nix-style.
- "C:\\Windows\\hax0rd.txt", # Absolute path, win-style.
- "C:/Windows/hax0rd.txt", # Absolute path, broken-style.
- "\\tmp\\hax0rd.txt", # Absolute path, broken in a different way.
- "/tmp\\hax0rd.txt", # Absolute path, broken by mixing.
- "subdir/hax0rd.txt", # Descendant path, *nix-style.
- "subdir\\hax0rd.txt", # Descendant path, win-style.
- "sub/dir\\hax0rd.txt", # Descendant path, mixed.
- "../../hax0rd.txt", # Relative path, *nix-style.
- "..\\..\\hax0rd.txt", # Relative path, win-style.
- "../..\\hax0rd.txt" # Relative path, mixed.
- ]
-
payload = client.FakePayload()
- for i, name in enumerate(scary_file_names):
+ for i, name in enumerate(CANDIDATE_TRAVERSAL_FILE_NAMES):
payload.write('\r\n'.join([
'--' + client.BOUNDARY,
'Content-Disposition: form-data; name="file%s"; filename="%s"' % (i, name),
@@ -252,7 +253,7 @@ class FileUploadTests(TestCase):
# The filenames should have been sanitized by the time it got to the view.
received = json.loads(response.content.decode('utf-8'))
- for i, name in enumerate(scary_file_names):
+ for i, name in enumerate(CANDIDATE_TRAVERSAL_FILE_NAMES):
got = received["file%s" % i]
self.assertEqual(got, "hax0rd.txt")
@@ -542,6 +543,36 @@ class FileUploadTests(TestCase):
# shouldn't differ.
self.assertEqual(os.path.basename(obj.testfile.path), 'MiXeD_cAsE.txt')
+ def test_filename_traversal_upload(self):
+ os.makedirs(UPLOAD_TO, exist_ok=True)
+ self.addCleanup(shutil.rmtree, MEDIA_ROOT)
+ file_name = '../test.txt',
+ payload = client.FakePayload()
+ payload.write(
+ '\r\n'.join([
+ '--' + client.BOUNDARY,
+ 'Content-Disposition: form-data; name="my_file"; '
+ 'filename="%s";' % file_name,
+ 'Content-Type: text/plain',
+ '',
+ 'file contents.\r\n',
+ '\r\n--' + client.BOUNDARY + '--\r\n',
+ ]),
+ )
+ r = {
+ 'CONTENT_LENGTH': len(payload),
+ 'CONTENT_TYPE': client.MULTIPART_CONTENT,
+ 'PATH_INFO': '/upload_traversal/',
+ 'REQUEST_METHOD': 'POST',
+ 'wsgi.input': payload,
+ }
+ response = self.client.request(**r)
+ result = response.json()
+ self.assertEqual(response.status_code, 200)
+ self.assertEqual(result['file_name'], 'test.txt')
+ self.assertIs(os.path.exists(os.path.join(MEDIA_ROOT, 'test.txt')), False)
+ self.assertIs(os.path.exists(os.path.join(UPLOAD_TO, 'test.txt')), True)
+
@override_settings(MEDIA_ROOT=MEDIA_ROOT)
class DirectoryCreationTests(TestCase):
@@ -598,6 +629,15 @@ class MultiParserTests(unittest.TestCase):
'CONTENT_LENGTH': '1'
}, StringIO('x'), [], 'utf-8')
+ def test_sanitize_file_name(self):
+ parser = MultiPartParser({
+ 'CONTENT_TYPE': 'multipart/form-data; boundary=_foo',
+ 'CONTENT_LENGTH': '1'
+ }, StringIO('x'), [], 'utf-8')
+ for file_name in CANDIDATE_TRAVERSAL_FILE_NAMES:
+ with self.subTest(file_name=file_name):
+ self.assertEqual(parser.sanitize_file_name(file_name), 'hax0rd.txt')
+
def test_rfc2231_parsing(self):
test_data = (
(b"Content-Type: application/x-stuff; title*=us-ascii'en-us'This%20is%20%2A%2A%2Afun%2A%2A%2A",
diff --git a/tests/file_uploads/uploadhandler.py b/tests/file_uploads/uploadhandler.py
index b69cc751cb02..7ceeded74bd5 100644
--- a/tests/file_uploads/uploadhandler.py
+++ b/tests/file_uploads/uploadhandler.py
@@ -1,6 +1,8 @@
"""
Upload handlers to test the upload API.
"""
+import os
+from tempfile import NamedTemporaryFile
from django.core.files.uploadhandler import FileUploadHandler, StopUpload
@@ -35,3 +37,32 @@ class ErroringUploadHandler(FileUploadHandler):
"""A handler that raises an exception."""
def receive_data_chunk(self, raw_data, start):
raise CustomUploadError("Oops!")
+
+
+class TraversalUploadHandler(FileUploadHandler):
+ """A handler with potential directory-traversal vulnerability."""
+ def __init__(self, request=None):
+ from .views import UPLOAD_TO
+
+ super().__init__(request)
+ self.upload_dir = UPLOAD_TO
+
+ def file_complete(self, file_size):
+ self.file.seek(0)
+ self.file.size = file_size
+ with open(os.path.join(self.upload_dir, self.file_name), 'wb') as fp:
+ fp.write(self.file.read())
+ return self.file
+
+ def new_file(
+ self, field_name, file_name, content_type, content_length, charset=None,
+ content_type_extra=None,
+ ):
+ super().new_file(
+ file_name, file_name, content_length, content_length, charset,
+ content_type_extra,
+ )
+ self.file = NamedTemporaryFile(suffix='.upload', dir=self.upload_dir)
+
+ def receive_data_chunk(self, raw_data, start):
+ self.file.write(raw_data)
diff --git a/tests/file_uploads/urls.py b/tests/file_uploads/urls.py
index 504554483e0d..632ab9969415 100644
--- a/tests/file_uploads/urls.py
+++ b/tests/file_uploads/urls.py
@@ -13,6 +13,7 @@ urlpatterns = [
url(r'^quota/broken/$', views.file_upload_quota_broken),
url(r'^getlist_count/$', views.file_upload_getlist_count),
url(r'^upload_errors/$', views.file_upload_errors),
+ url(r'^upload_traversal/$', views.file_upload_traversal_view),
url(r'^filename_case/$', views.file_upload_filename_case_view),
url(r'^fd_closing/(?P<access>t|f)/$', views.file_upload_fd_closing),
]
diff --git a/tests/file_uploads/views.py b/tests/file_uploads/views.py
index 5269e98da770..f36dc4f7d03d 100644
--- a/tests/file_uploads/views.py
+++ b/tests/file_uploads/views.py
@@ -11,7 +11,9 @@ from django.utils.encoding import force_bytes, smart_str
from .models import FileModel
from .tests import UNICODE_FILENAME, UPLOAD_TO
-from .uploadhandler import ErroringUploadHandler, QuotaUploadHandler
+from .uploadhandler import (
+ ErroringUploadHandler, QuotaUploadHandler, TraversalUploadHandler,
+)
def file_upload_view(request):
@@ -163,3 +165,11 @@ def file_upload_fd_closing(request, access):
if access == 't':
request.FILES # Trigger file parsing.
return HttpResponse('')
+
+
+def file_upload_traversal_view(request):
+ request.upload_handlers.insert(0, TraversalUploadHandler())
+ request.FILES # Trigger file parsing.
+ return JsonResponse(
+ {'file_name': request.upload_handlers[0].file_name},
+ )
