python3-urllib3: patch CVE-2025-66418

Pick patch per [1].

[1] https://nvd.nist.gov/vuln/detail/CVE-2025-66418

(From OE-Core rev: 469fcdd5f07635fa9e308c968126807c1ca09647)

Signed-off-by: Peter Marko <peter.marko@siemens.com>
Signed-off-by: Yoann Congal <yoann.congal@smile.fr>
Signed-off-by: Paul Barker <paul@pbarker.dev>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
This commit is contained in:
Peter Marko
2026-01-20 14:52:43 +01:00
committed by Richard Purdie
parent 842275784a
commit 4c8419bebe
2 changed files with 75 additions and 0 deletions

View File

@@ -0,0 +1,74 @@
From 24d7b67eac89f94e11003424bcf0d8f7b72222a8 Mon Sep 17 00:00:00 2001
From: Illia Volochii <illia.volochii@gmail.com>
Date: Fri, 5 Dec 2025 16:41:33 +0200
Subject: [PATCH] Merge commit from fork
* Add a hard-coded limit for the decompression chain
* Reuse new list
CVE: CVE-2025-66418
Upstream-Status: Backport [https://github.com/urllib3/urllib3/commit/24d7b67eac89f94e11003424bcf0d8f7b72222a8]
Signed-off-by: Peter Marko <peter.marko@siemens.com>
---
changelog/GHSA-gm62-xv2j-4w53.security.rst | 4 ++++
src/urllib3/response.py | 12 +++++++++++-
test/test_response.py | 10 ++++++++++
3 files changed, 25 insertions(+), 1 deletion(-)
create mode 100644 changelog/GHSA-gm62-xv2j-4w53.security.rst
diff --git a/changelog/GHSA-gm62-xv2j-4w53.security.rst b/changelog/GHSA-gm62-xv2j-4w53.security.rst
new file mode 100644
index 00000000..6646eaa3
--- /dev/null
+++ b/changelog/GHSA-gm62-xv2j-4w53.security.rst
@@ -0,0 +1,4 @@
+Fixed a security issue where an attacker could compose an HTTP response with
+virtually unlimited links in the ``Content-Encoding`` header, potentially
+leading to a denial of service (DoS) attack by exhausting system resources
+during decoding. The number of allowed chained encodings is now limited to 5.
diff --git a/src/urllib3/response.py b/src/urllib3/response.py
index 4ba42136..069f726c 100644
--- a/src/urllib3/response.py
+++ b/src/urllib3/response.py
@@ -135,8 +135,18 @@ class MultiDecoder(object):
they were applied.
"""
+ # Maximum allowed number of chained HTTP encodings in the
+ # Content-Encoding header.
+ max_decode_links = 5
+
def __init__(self, modes):
- self._decoders = [_get_decoder(m.strip()) for m in modes.split(",")]
+ encodings = [m.strip() for m in modes.split(",")]
+ if len(encodings) > self.max_decode_links:
+ raise DecodeError(
+ "Too many content encodings in the chain: "
+ f"{len(encodings)} > {self.max_decode_links}"
+ )
+ self._decoders = [_get_decoder(e) for e in encodings]
def flush(self):
return self._decoders[0].flush()
diff --git a/test/test_response.py b/test/test_response.py
index 9592fdd9..d824ae70 100644
--- a/test/test_response.py
+++ b/test/test_response.py
@@ -295,6 +295,16 @@ class TestResponse(object):
assert r.data == b"foo"
+ def test_read_multi_decoding_too_many_links(self) -> None:
+ fp = BytesIO(b"foo")
+ with pytest.raises(
+ DecodeError, match="Too many content encodings in the chain: 6 > 5"
+ ):
+ HTTPResponse(
+ fp,
+ headers={"content-encoding": "gzip, deflate, br, zstd, gzip, deflate"},
+ )
+
def test_body_blob(self):
resp = HTTPResponse(b"foo")
assert resp.data == b"foo"

View File

@@ -9,6 +9,7 @@ inherit pypi setuptools3
SRC_URI += " \
file://CVE-2025-50181.patch \
file://CVE-2025-66418.patch \
"
RDEPENDS:${PN} += "\