diff mbox series

[meta-python,wrynose,1/6] python3-pyjwt: Fix CVE-2026-48522

Message ID 20260819110016.252278-1-hthakar@cisco.com
State New
Headers show
Series [meta-python,wrynose,1/6] python3-pyjwt: Fix CVE-2026-48522 | expand

Commit Message

From: Hetvi Thakar <hthakar@cisco.com>

This patch applies the upstream 2.13.0 backport for
CVE-2026-48522. The upstream fix commit is referenced in [1],
and the public CVE advisory is referenced in [2].

[1] https://github.com/jpadilla/pyjwt/commit/95791b1759b8aa4f2203575d344d5c78564cdc81
[2] https://github.com/advisories/GHSA-993g-76c3-p5m4

Signed-off-by: Hetvi Thakar <hthakar@cisco.com>
---
 .../python/files/CVE-2026-48522.patch         | 126 ++++++++++++++++++
 .../python/python3-pyjwt_2.12.1.bb            |   2 +
 2 files changed, 128 insertions(+)
 create mode 100644 meta-python/recipes-devtools/python/files/CVE-2026-48522.patch
diff mbox series

Patch

diff --git a/meta-python/recipes-devtools/python/files/CVE-2026-48522.patch b/meta-python/recipes-devtools/python/files/CVE-2026-48522.patch
new file mode 100644
index 0000000000..c1e6466d35
--- /dev/null
+++ b/meta-python/recipes-devtools/python/files/CVE-2026-48522.patch
@@ -0,0 +1,126 @@ 
+From f369d32169410b17717d2a9c00d5bf3ac655c85d Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Jos=C3=A9=20Padilla?= <jpadilla@users.noreply.github.com>
+Date: Thu, 21 May 2026 14:11:10 -0400
+Subject: [PATCH] Bundle security fixes and hardening into 2.13.0
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Security:
+- `HMACAlgorithm.prepare_key` rejects JWK JSON documents passed as raw
+  HMAC secrets to close an algorithm-confusion gap not covered by the
+  existing PEM/SSH guard. Reported by @aradona91 in GHSA-xgmm-8j9v-c9wx.
+- Bind the JWT header `alg` to `PyJWK.algorithm_name` during verification
+  so the caller's `algorithms` allow-list cannot be bypassed when decoding
+  with a `PyJWK` / `PyJWKClient` key. Reported by @sushi-gif in
+  GHSA-jq35-7prp-9v3f.
+- Skip the unconditional base64 decode of the compact-form payload
+  segment when `b64=false` is set, and require that segment to be empty
+  (RFC 7515 Appendix F detached form). Closes an unauthenticated DoS
+  amplifier. Reported by @thesmartshadow in GHSA-w7vc-732c-9m39.
+- `PyJWKClient` rejects any URI whose scheme is not `http` or `https` so
+  attacker-influenced URIs cannot read local files or reach unintended
+  schemes via urllib's default `file://` / `ftp://` / `data:` handlers.
+  Reported by @KEIJOT in GHSA-993g-76c3-p5m4.
+- Preserve the cached JWK Set on fetch errors in `PyJWKClient.fetch_data`.
+  The previous `finally`-block `put(None)` pattern cleared the cache on
+  any transient outage. Reported by @eddieran in GHSA-fhv5-28vv-h8m8.
+
+Fixes:
+- Reject empty HMAC keys outright in `HMACAlgorithm.prepare_key` with
+  `InvalidKeyError` instead of accepting them with only a warning.
+  Hardening prompted by reports from @SnailSploit and @spartan8806.
+- Forward per-call `options` (including `enforce_minimum_key_length`)
+  from `PyJWT.decode` through to `PyJWS._verify_signature`. Thanks to
+  @WLUB.
+- RFC 7797 §3 compliance for `b64=false`: encoder auto-adds `"b64"` to
+  `crit`; decoder rejects tokens that set `b64=false` without listing
+  it in `crit`. Thanks to @MachineLearning-Nerd.
+
+CVE: CVE-2026-48522
+Upstream-Status: Backport [https://github.com/jpadilla/pyjwt/commit/95791b1759b8aa4f2203575d344d5c78564cdc81]
+
+Backport Changes:
+- Split out the PyJWKClient URI-scheme validation because the upstream
+  commit bundles multiple CVEs.
+- Omitted CHANGELOG.rst because it conflicted and is release documentation.
+- Omitted the 2.13.0 version bump and other bundled fixes; applicable CVE
+  fixes are carried in separate patches.
+
+(cherry picked from commit 95791b1759b8aa4f2203575d344d5c78564cdc81)
+Signed-off-by: Hetvi Thakar <hthakar@cisco.com>
+---
+ jwt/jwks_client.py        | 11 +++++++++++
+ tests/test_jwks_client.py | 30 ++++++++++++++++++++++++++++++
+ 2 files changed, 41 insertions(+)
+
+diff --git a/jwt/jwks_client.py b/jwt/jwks_client.py
+index b81e8f4..8d1b0c4 100644
+--- a/jwt/jwks_client.py
++++ b/jwt/jwks_client.py
+@@ -6,6 +6,7 @@ from functools import lru_cache
+ from ssl import SSLContext
+ from typing import Any
+ from urllib.error import HTTPError, URLError
++from urllib.parse import urlparse
+ 
+ from .api_jwk import PyJWK, PyJWKSet
+ from .api_jwt import decode_complete as decode_token
+@@ -69,6 +70,16 @@ class PyJWKClient:
+         """
+         if headers is None:
+             headers = {}
++        # urllib's default OpenerDirector also handles file://, ftp://, and
++        # data: URIs. Reject anything that isn't http(s) eagerly so a caller
++        # passing an attacker-influenced URL (e.g. taken from a `jku` token
++        # header) can't read local files or reach other unintended schemes.
++        scheme = urlparse(uri).scheme.lower()
++        if scheme not in ("http", "https"):
++            raise PyJWKClientError(
++                f"Invalid JWKS URI scheme {scheme!r}: only 'http' and 'https' "
++                f"are supported."
++            )
+         self.uri = uri
+         self.jwk_set_cache: JWKSetCache | None = None
+         self.headers = headers
+diff --git a/tests/test_jwks_client.py b/tests/test_jwks_client.py
+index ceee672..d6793cc 100644
+--- a/tests/test_jwks_client.py
++++ b/tests/test_jwks_client.py
+@@ -344,6 +344,36 @@ class TestPyJWKClient:
+             jwks_client = PyJWKClient(url, lifespan=-1)
+             assert jwks_client is None
+ 
++    @pytest.mark.parametrize(
++        "uri",
++        [
++            "file:///etc/passwd",
++            "ftp://example.org/keys.json",
++            'data:application/json,{"keys":[]}',
++            "/etc/passwd",  # urlparse gives scheme="" — also rejected
++            "ldap://internal.test/jwks",
++        ],
++    )
++    def test_pyjwkclient_rejects_non_http_schemes(self, uri: str) -> None:
++        # urllib's default OpenerDirector handles file://, ftp://, and data:
++        # URIs. PyJWKClient must reject these so callers can't be tricked
++        # into reading attacker-controlled local files or other unintended
++        # schemes via a manipulated URI.
++        with pytest.raises(PyJWKClientError, match="Invalid JWKS URI scheme"):
++            PyJWKClient(uri)
++
++    @pytest.mark.parametrize(
++        "uri",
++        [
++            "http://localhost/jwks.json",
++            "https://example.test/jwks.json",
++            "HTTPS://Example.Test/jwks.json",  # case-insensitive
++        ],
++    )
++    def test_pyjwkclient_accepts_http_https_schemes(self, uri: str) -> None:
++        # Construction succeeds; no fetch is made until get_jwk_set().
++        PyJWKClient(uri)
++
+     def test_get_jwt_set_timeout(self) -> None:
+         url = "https://dev-87evx9ru.auth0.com/.well-known/jwks.json"
+         jwks_client = PyJWKClient(url, timeout=5)
diff --git a/meta-python/recipes-devtools/python/python3-pyjwt_2.12.1.bb b/meta-python/recipes-devtools/python/python3-pyjwt_2.12.1.bb
index eb445f9c91..ed7a280ee5 100644
--- a/meta-python/recipes-devtools/python/python3-pyjwt_2.12.1.bb
+++ b/meta-python/recipes-devtools/python/python3-pyjwt_2.12.1.bb
@@ -5,6 +5,8 @@  HOMEPAGE = "https://github.com/jpadilla/pyjwt"
 LICENSE = "MIT"
 LIC_FILES_CHKSUM = "file://LICENSE;md5=e4b56d2c9973d8cf54655555be06e551"
 
+SRC_URI += "file://CVE-2026-48522.patch"
+
 SRC_URI[sha256sum] = "c74a7a2adf861c04d002db713dd85f84beb242228e671280bf709d765b03672b"
 
 PYPI_PACKAGE = "pyjwt"