Version in base suite: 1.26.12-1+deb12u3 Base version: python-urllib3_1.26.12-1+deb12u3 Target version: python-urllib3_1.26.12-1+deb12u4 Base file: /srv/ftp-master.debian.org/ftp/pool/main/p/python-urllib3/python-urllib3_1.26.12-1+deb12u3.dsc Target file: /srv/ftp-master.debian.org/policy/pool/main/p/python-urllib3/python-urllib3_1.26.12-1+deb12u4.dsc changelog | 8 ++ patches/CVE-2026-44431.patch | 127 +++++++++++++++++++++++++++++++++++++++++++ patches/series | 1 3 files changed, 136 insertions(+) dpkg-source: warning: cannot verify inline signature for /srv/release.debian.org/tmp/tmpz2j3wxyn/python-urllib3_1.26.12-1+deb12u3.dsc: no acceptable signature found dpkg-source: warning: cannot verify inline signature for /srv/release.debian.org/tmp/tmpz2j3wxyn/python-urllib3_1.26.12-1+deb12u4.dsc: no acceptable signature found diff -Nru python-urllib3-1.26.12/debian/changelog python-urllib3-1.26.12/debian/changelog --- python-urllib3-1.26.12/debian/changelog 2026-01-20 21:34:53.000000000 +0000 +++ python-urllib3-1.26.12/debian/changelog 2026-06-26 05:01:27.000000000 +0000 @@ -1,3 +1,11 @@ +python-urllib3 (1.26.12-1+deb12u4) bookworm-security; urgency=high + + * Non-maintainer upload by the LTS Team. + * Fix CVE-2026-44431: Sensitive headers forwarded across origins in proxied + low-level redirects. (Closes: #1136653) + + -- Guilhem Moulin Fri, 26 Jun 2026 07:01:27 +0200 + python-urllib3 (1.26.12-1+deb12u3) bookworm-security; urgency=high * Non-maintainer upload by the Security Team. diff -Nru python-urllib3-1.26.12/debian/patches/CVE-2026-44431.patch python-urllib3-1.26.12/debian/patches/CVE-2026-44431.patch --- python-urllib3-1.26.12/debian/patches/CVE-2026-44431.patch 1970-01-01 00:00:00.000000000 +0000 +++ python-urllib3-1.26.12/debian/patches/CVE-2026-44431.patch 2026-06-26 05:01:27.000000000 +0000 @@ -0,0 +1,127 @@ +From: Illia Volochii +Date: Thu, 7 May 2026 18:40:31 +0300 +Subject: Remove sensitive headers in proxy pools too + +Co-authored-by: Copilot +Origin: https://github.com/urllib3/urllib3/commit/5ec0de499b9166ca71c65ab04f2a7e4eb0d66fcc +Bug: https://github.com/urllib3/urllib3/security/advisories/GHSA-qccp-gfcp-xxvc +Bug-Debian: https://bugs.debian.org/1136653 +Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2026-44431 +--- + src/urllib3/connectionpool.py | 12 +++++ + test/with_dummyserver/test_proxy_poolmanager.py | 72 +++++++++++++++++++++++++ + 2 files changed, 84 insertions(+) + +diff --git a/src/urllib3/connectionpool.py b/src/urllib3/connectionpool.py +index 06aa8b8..1873312 100644 +--- a/src/urllib3/connectionpool.py ++++ b/src/urllib3/connectionpool.py +@@ -840,6 +840,18 @@ class HTTPConnectionPool(ConnectionPool, RequestMethods): + body = None + headers = HTTPHeaderDict(headers)._prepare_for_method_change() + ++ # Strip headers marked as unsafe to forward to the redirected location. ++ # Check remove_headers_on_redirect to avoid a potential network call within ++ # self.is_same_host() which may use socket.gethostbyname() in the future. ++ if retries.remove_headers_on_redirect and not self.is_same_host( ++ redirect_location ++ ): ++ new_headers = headers.copy() # type: ignore[union-attr] ++ for header in headers: ++ if header.lower() in retries.remove_headers_on_redirect: ++ new_headers.pop(header, None) ++ headers = new_headers ++ + try: + retries = retries.increment(method, url, response=response, _pool=self) + except MaxRetryError: +diff --git a/test/with_dummyserver/test_proxy_poolmanager.py b/test/with_dummyserver/test_proxy_poolmanager.py +index 7b292a2..0af6fed 100644 +--- a/test/with_dummyserver/test_proxy_poolmanager.py ++++ b/test/with_dummyserver/test_proxy_poolmanager.py +@@ -34,6 +34,7 @@ from urllib3.exceptions import ( + SubjectAltNameWarning, + ) + from urllib3.poolmanager import ProxyManager, proxy_from_url ++from urllib3.util.retry import RequestHistory + from urllib3.util import Timeout + from urllib3.util.ssl_ import create_urllib3_context + +@@ -277,6 +278,77 @@ class TestHTTPProxyManager(HTTPDummyProxyTestCase): + ) + assert r._pool.host != self.http_host_alt + ++ _sensitive_headers = { ++ "Authorization": "foo", ++ "Proxy-Authorization": "bar", ++ "Cookie": "foo=bar", ++ } ++ ++ @pytest.mark.parametrize( ++ "sensitive_headers", ++ (_sensitive_headers, {k.lower(): v for k, v in _sensitive_headers.items()}), ++ ids=("capitalized", "lowercase"), ++ ) ++ def test_cross_host_redirect_remove_headers_via_proxy_manager( ++ self, sensitive_headers: dict[str, str] ++ ) -> None: ++ headers_url = f"{self.http_url_alt}/headers" ++ initial_url = f"{self.http_url}/redirect?target={headers_url}" ++ with proxy_from_url(self.proxy_url) as proxy_mgr: ++ r = proxy_mgr.request( ++ "GET", initial_url, headers=sensitive_headers, retries=1 ++ ) ++ assert r.status == 200 ++ assert r.retries is not None ++ assert r.retries.history == ( ++ RequestHistory( ++ method="GET", ++ url=initial_url, ++ error=None, ++ status=303, ++ redirect_location=headers_url, ++ ), ++ ) ++ data = json.loads(r.data.decode("utf-8")) ++ for header in sensitive_headers: ++ assert header not in data ++ ++ @pytest.mark.parametrize( ++ "sensitive_headers", ++ (_sensitive_headers, {k.lower(): v for k, v in _sensitive_headers.items()}), ++ ids=("capitalized", "lowercase"), ++ ) ++ def test_cross_host_redirect_remove_headers_via_pool( ++ self, sensitive_headers: dict[str, str] ++ ) -> None: ++ headers_url = f"{self.http_url_alt}/headers" ++ initial_url = f"{self.http_url}/redirect?target={headers_url}" ++ with proxy_from_url(self.proxy_url) as proxy_mgr: ++ pool = proxy_mgr.connection_from_url(self.http_url) ++ r = pool.urlopen( ++ "GET", ++ initial_url, ++ headers=sensitive_headers, ++ retries=1, ++ redirect=True, ++ assert_same_host=False, ++ preload_content=True, ++ ) ++ assert r.status == 200 ++ assert r.retries is not None ++ assert r.retries.history == ( ++ RequestHistory( ++ method="GET", ++ url=initial_url, ++ error=None, ++ status=303, ++ redirect_location=headers_url, ++ ), ++ ) ++ data = json.loads(r.data.decode("utf-8")) ++ for header in sensitive_headers: ++ assert header not in data ++ + def test_cross_protocol_redirect(self): + with proxy_from_url(self.proxy_url, ca_certs=DEFAULT_CA) as http: + cross_protocol_location = "%s/echo?a=b" % self.https_url diff -Nru python-urllib3-1.26.12/debian/patches/series python-urllib3-1.26.12/debian/patches/series --- python-urllib3-1.26.12/debian/patches/series 2026-01-20 21:27:46.000000000 +0000 +++ python-urllib3-1.26.12/debian/patches/series 2026-06-26 05:01:27.000000000 +0000 @@ -9,3 +9,4 @@ Prevent-issue-in-HTTPResponse-.read-when-decoded_con.patch fix-missed-coverage-when-calling-read-having-amt-Non.patch apply-suggestion-from-pquentin.patch +CVE-2026-44431.patch