99 lines
4.8 KiB
Diff
99 lines
4.8 KiB
Diff
From e42be9b593f1d5e83a947f73058b919395398424 Mon Sep 17 00:00:00 2001
|
|
From: Julian Berman <Julian+Hg@GrayVines.com>
|
|
Date: Fri, 23 Sep 2022 11:30:55 +0200
|
|
Subject: [PATCH] Pull in the http.server vulnerability fix from
|
|
python/cpython#87389
|
|
|
|
Fixes an open redirection vulnerability for paths starting with `//`.
|
|
|
|
Closes: #3812
|
|
|
|
--HG--
|
|
branch : http_server_vuln_fix
|
|
---
|
|
lib-python/3/http/server.py | 7 ++++
|
|
lib-python/3/test/test_httpservers.py | 49 +++++++++++++++++++++++++++
|
|
2 files changed, 56 insertions(+)
|
|
|
|
diff --git a/lib-python/3/http/server.py b/lib-python/3/http/server.py
|
|
index 38f7accad7..39de35458c 100644
|
|
--- a/lib-python/3/http/server.py
|
|
+++ b/lib-python/3/http/server.py
|
|
@@ -332,6 +332,13 @@ class BaseHTTPRequestHandler(socketserver.StreamRequestHandler):
|
|
return False
|
|
self.command, self.path = command, path
|
|
|
|
+ # gh-87389: The purpose of replacing '//' with '/' is to protect
|
|
+ # against open redirect attacks possibly triggered if the path starts
|
|
+ # with '//' because http clients treat //path as an absolute URI
|
|
+ # without scheme (similar to http://path) rather than a path.
|
|
+ if self.path.startswith('//'):
|
|
+ self.path = '/' + self.path.lstrip('/') # Reduce to a single /
|
|
+
|
|
# Examine the headers and look for a Connection directive.
|
|
try:
|
|
self.headers = http.client.parse_headers(self.rfile,
|
|
diff --git a/lib-python/3/test/test_httpservers.py b/lib-python/3/test/test_httpservers.py
|
|
index c5b833723e..97dae7a7ce 100644
|
|
--- a/lib-python/3/test/test_httpservers.py
|
|
+++ b/lib-python/3/test/test_httpservers.py
|
|
@@ -416,6 +416,55 @@ class SimpleHTTPServerTestCase(BaseTestCase):
|
|
self.check_status_and_reason(response, HTTPStatus.OK,
|
|
data=support.TESTFN_UNDECODABLE)
|
|
|
|
+ def test_get_dir_redirect_location_domain_injection_bug(self):
|
|
+ """Ensure //evil.co/..%2f../../X does not put //evil.co/ in Location.
|
|
+
|
|
+ //netloc/ in a Location header is a redirect to a new host.
|
|
+ https://github.com/python/cpython/issues/87389
|
|
+
|
|
+ This checks that a path resolving to a directory on our server cannot
|
|
+ resolve into a redirect to another server.
|
|
+ """
|
|
+ os.mkdir(os.path.join(self.tempdir, 'existing_directory'))
|
|
+ url = f'/python.org/..%2f..%2f..%2f..%2f..%2f../%0a%0d/../{self.tempdir_name}/existing_directory'
|
|
+ expected_location = f'{url}/' # /python.org.../ single slash single prefix, trailing slash
|
|
+ # Canonicalizes to /tmp/tempdir_name/existing_directory which does
|
|
+ # exist and is a dir, triggering the 301 redirect logic.
|
|
+ response = self.request(url)
|
|
+ self.check_status_and_reason(response, HTTPStatus.MOVED_PERMANENTLY)
|
|
+ location = response.getheader('Location')
|
|
+ self.assertEqual(location, expected_location, msg='non-attack failed!')
|
|
+
|
|
+ # //python.org... multi-slash prefix, no trailing slash
|
|
+ attack_url = f'/{url}'
|
|
+ response = self.request(attack_url)
|
|
+ self.check_status_and_reason(response, HTTPStatus.MOVED_PERMANENTLY)
|
|
+ location = response.getheader('Location')
|
|
+ self.assertFalse(location.startswith('//'), msg=location)
|
|
+ self.assertEqual(location, expected_location,
|
|
+ msg='Expected Location header to start with a single / and '
|
|
+ 'end with a / as this is a directory redirect.')
|
|
+
|
|
+ # ///python.org... triple-slash prefix, no trailing slash
|
|
+ attack3_url = f'//{url}'
|
|
+ response = self.request(attack3_url)
|
|
+ self.check_status_and_reason(response, HTTPStatus.MOVED_PERMANENTLY)
|
|
+ self.assertEqual(response.getheader('Location'), expected_location)
|
|
+
|
|
+ # If the second word in the http request (Request-URI for the http
|
|
+ # method) is a full URI, we don't worry about it, as that'll be parsed
|
|
+ # and reassembled as a full URI within BaseHTTPRequestHandler.send_head
|
|
+ # so no errant scheme-less //netloc//evil.co/ domain mixup can happen.
|
|
+ attack_scheme_netloc_2slash_url = f'https://pypi.org/{url}'
|
|
+ expected_scheme_netloc_location = f'{attack_scheme_netloc_2slash_url}/'
|
|
+ response = self.request(attack_scheme_netloc_2slash_url)
|
|
+ self.check_status_and_reason(response, HTTPStatus.MOVED_PERMANENTLY)
|
|
+ location = response.getheader('Location')
|
|
+ # We're just ensuring that the scheme and domain make it through, if
|
|
+ # there are or aren't multiple slashes at the start of the path that
|
|
+ # follows that isn't important in this Location: header.
|
|
+ self.assertTrue(location.startswith('https://pypi.org/'), msg=location)
|
|
+
|
|
def test_get(self):
|
|
#constructs the path relative to the root directory of the HTTPServer
|
|
response = self.request(self.base_url + '/test')
|
|
--
|
|
GitLab
|
|
|