Fix CVE-2023-6681

CVE-2023-6681.patch

@@ -0,0 +1,67 @@
+From d2655d370586cb830e49acfb450f87598da60be8 Mon Sep 17 00:00:00 2001
+From: Simo Sorce <simo@redhat.com>
+Date: Thu, 7 Dec 2023 12:49:07 -0500
+Subject: [PATCH] Fix potential DoS issue with p2c header
+
+Unbounded p2c headers may be used to cause an application that accept
+PBES algorithms to spend alot of resources running PBKDF2 with a very
+high number of iterations.
+
+Clamp the default maximum to 16384 (double the default of 8192).
+An application that wants to use more iterations will have to chenge the
+jwa default max.
+
+Fixes CVE-2023-6681
+
+Signed-off-by: Simo Sorce <simo@redhat.com>
+---
+ jwcrypto/jwa.py   |  5 +++++
+ jwcrypto/tests.py | 12 ++++++++++++
+ 2 files changed, 17 insertions(+)
+
+diff --git a/jwcrypto/jwa.py b/jwcrypto/jwa.py
+index de7a79f..ca4568e 100644
+--- a/jwcrypto/jwa.py
++++ b/jwcrypto/jwa.py
+@@ -28,6 +28,8 @@
+ 
+ # Implements RFC 7518 - JSON Web Algorithms (JWA)
+ 
++default_max_pbkdf2_iterations = 16384
++
+ 
+ class JWAAlgorithm(metaclass=ABCMeta):
+ 
+@@ -588,6 +590,9 @@ def __init__(self):
+         self.aeskwmap = {128: _A128KW, 192: _A192KW, 256: _A256KW}
+ 
+     def _get_key(self, alg, key, p2s, p2c):
++        if p2c > default_max_pbkdf2_iterations:
++            raise ValueError('Invalid p2c value, too large')
++
+         if not isinstance(key, JWK):
+             # backwards compatibility for old interface
+             if isinstance(key, bytes):
+diff --git a/jwcrypto/tests.py b/jwcrypto/tests.py
+index 6069fab..bb2ff10 100644
+--- a/jwcrypto/tests.py
++++ b/jwcrypto/tests.py
+@@ -2099,6 +2099,18 @@ def test_pbes2_hs256_aeskw_custom_params(self):
+         key = jwk.JWK.from_password('password')
+         self.assertRaises(ValueError, enc.add_recipient, key)
+ 
++        # Test p2c iteration checks
++        maxiter = jwa.default_max_pbkdf2_iterations
++        p2cenc = jwe.JWE(plaintext='plain',
++                         protected={"alg": "PBES2-HS256+A128KW",
++                                    "enc": "A256CBC-HS512",
++                                    "p2c": maxiter + 1,
++                                    "p2s": base64url_encode("A" * 16)})
++        with self.assertRaisesRegex(ValueError, 'too large'):
++            p2cenc.add_recipient(key)
++        jwa.default_max_pbkdf2_iterations += 2
++        p2cenc.add_recipient(key)
++
+ 
+ class JWATests(unittest.TestCase):
+     def test_jwa_create(self):

python-jwcrypto.spec

@@ -1,10 +1,12 @@
 Name:           python-jwcrypto
 Version:        1.4.2
-Release:        1
+Release:        2
 Summary:        Implements JWK, JWS, JWE specifications with python-cryptography
 License:        LGPLv3+
 URL:            https://github.com/latchset/jwcrypto
 Source0:        https://github.com/latchset/jwcrypto/releases/download/v%{version}/jwcrypto-%{version}.tar.gz
+# https://github.com/latchset/jwcrypto/commit/d2655d370586cb830e49acfb450f87598da60be8
+Patch0:         CVE-2023-6681.patch
 
 BuildArch:      noarch
 BuildRequires:  python%{python3_pkgversion}-devel python%{python3_pkgversion}-setuptools
@@ -42,6 +44,9 @@ Implements JWK, JWS, JWE specifications using python-cryptography
 %{python3_sitelib}/jwcrypto-%{version}-py%{python3_version}.egg-info
 
 %changelog
+* Fri Dec 29 2023 yaoxin <yao_xin001@hoperun.com> - 1.4.2-2
+- Fix CVE-2023-6681
+
 * Wed Dec 20 2023 yaoxin <yao_xin001@hoperun.com> - 1.4.2-1
 - Upgrade to 1.4.2 for fix CVE-2022-3102