diff mbox series

[mickledore,1/1] python3-cryptography: fix CVE-2023-49083

Message ID 20231207115815.532553-1-narpat.mali@windriver.com
State New
Headers show
Series [mickledore,1/1] python3-cryptography: fix CVE-2023-49083 | expand

Commit Message

nmali Dec. 7, 2023, 11:58 a.m. UTC 
From: Narpat Mali <narpat.mali@windriver.com>

cryptography is a package designed to expose cryptographic primitives
and recipes to Python developers. Calling `load_pem_pkcs7_certificates`
or `load_der_pkcs7_certificates` could lead to a NULL-pointer dereference
and segfault. Exploitation of this vulnerability poses a serious risk of
Denial of Service (DoS) for any application attempting to deserialize a
PKCS7 blob/certificate. The consequences extend to potential disruptions
in system availability and stability. This vulnerability has been patched
in version 41.0.6.

References:
https://nvd.nist.gov/vuln/detail/CVE-2023-49083
https://security-tracker.debian.org/tracker/CVE-2023-49083

Signed-off-by: Narpat Mali <narpat.mali@windriver.com>
---
 .../python3-cryptography/CVE-2023-49083.patch | 53 +++++++++++++++++++
 .../python/python3-cryptography_39.0.2.bb     |  1 +
 2 files changed, 54 insertions(+)
 create mode 100644 meta/recipes-devtools/python/python3-cryptography/CVE-2023-49083.patch

Comments

Yoann Congal Dec. 7, 2023, 12:15 p.m. UTC | #1 
Hi,

Le 07/12/2023 à 12:58, Narpat Mali via lists.openembedded.org a écrit :
> From: Narpat Mali <narpat.mali@windriver.com>
> 
> cryptography is a package designed to expose cryptographic primitives
> and recipes to Python developers. Calling `load_pem_pkcs7_certificates`
> or `load_der_pkcs7_certificates` could lead to a NULL-pointer dereference
> and segfault. Exploitation of this vulnerability poses a serious risk of
> Denial of Service (DoS) for any application attempting to deserialize a
> PKCS7 blob/certificate. The consequences extend to potential disruptions
> in system availability and stability. This vulnerability has been patched
> in version 41.0.6.
> 
> References:
> https://nvd.nist.gov/vuln/detail/CVE-2023-49083
> https://security-tracker.debian.org/tracker/CVE-2023-49083
> 
> Signed-off-by: Narpat Mali <narpat.mali@windriver.com>

FYI, this is a patch for mickledore branch but this branch is EOL (End-of-life). See :
https://wiki.yoctoproject.org/wiki/Stable_Release_and_LTS#LTS_.E2.80.9CMixin.E2.80.9D_repositories
https://wiki.yoctoproject.org/wiki/Releases

Regards,
diff mbox series

Patch

diff --git a/meta/recipes-devtools/python/python3-cryptography/CVE-2023-49083.patch b/meta/recipes-devtools/python/python3-cryptography/CVE-2023-49083.patch
new file mode 100644
index 0000000000..3870529ecc
--- /dev/null
+++ b/meta/recipes-devtools/python/python3-cryptography/CVE-2023-49083.patch
@@ -0,0 +1,53 @@ 
+From df089065abde07b9b2666693c10f4d5c96cd99a1 Mon Sep 17 00:00:00 2001
+From: Alex Gaynor <alex.gaynor@gmail.com>
+Date: Thu, 7 Dec 2023 09:33:46 +0000
+Subject: [PATCH] Fixed crash when loading a PKCS#7 bundle with no certificates
+ (#9926)
+
+CVE: CVE-2023-49083
+
+Upstream-Status: Backport [https://github.com/pyca/cryptography/commit/1e7b4d074e14c4e694d3ce69ad6754a6039fd6ff]
+
+Signed-off-by: Narpat Mali <narpat.mali@windriver.com>
+---
+ src/cryptography/hazmat/backends/openssl/backend.py | 5 ++++-
+ tests/hazmat/primitives/test_pkcs7.py               | 6 ++++++
+ 2 files changed, 10 insertions(+), 1 deletion(-)
+
+diff --git a/src/cryptography/hazmat/backends/openssl/backend.py b/src/cryptography/hazmat/backends/openssl/backend.py
+index 48f4265..7b949be 100644
+--- a/src/cryptography/hazmat/backends/openssl/backend.py
++++ b/src/cryptography/hazmat/backends/openssl/backend.py
+@@ -2466,9 +2466,12 @@ class Backend:
+                 _Reasons.UNSUPPORTED_SERIALIZATION,
+             )
+
++        certs: list[x509.Certificate] = []
++        if p7.d.sign == self._ffi.NULL:
++            return certs
++
+         sk_x509 = p7.d.sign.cert
+         num = self._lib.sk_X509_num(sk_x509)
+-        certs = []
+         for i in range(num):
+             x509 = self._lib.sk_X509_value(sk_x509, i)
+             self.openssl_assert(x509 != self._ffi.NULL)
+diff --git a/tests/hazmat/primitives/test_pkcs7.py b/tests/hazmat/primitives/test_pkcs7.py
+index d879563..36ce031 100644
+--- a/tests/hazmat/primitives/test_pkcs7.py
++++ b/tests/hazmat/primitives/test_pkcs7.py
+@@ -89,6 +89,12 @@ class TestPKCS7Loading:
+                 mode="rb",
+             )
+
++    def test_load_pkcs7_empty_certificates(self):
++        der = b"\x30\x0B\x06\x09\x2A\x86\x48\x86\xF7\x0D\x01\x07\x02"
++
++        certificates = pkcs7.load_der_pkcs7_certificates(der)
++        assert certificates == []
++
+
+ # We have no public verification API and won't be adding one until we get
+ # some requirements from users so this function exists to give us basic
+--
+2.40.0
diff --git a/meta/recipes-devtools/python/python3-cryptography_39.0.2.bb b/meta/recipes-devtools/python/python3-cryptography_39.0.2.bb
index 449e3ba1bc..b54c7e1719 100644
--- a/meta/recipes-devtools/python/python3-cryptography_39.0.2.bb
+++ b/meta/recipes-devtools/python/python3-cryptography_39.0.2.bb
@@ -16,6 +16,7 @@  SRC_URI += "\
     file://0001-pyproject.toml-remove-benchmark-disable-option.patch \
     file://check-memfree.py \
     file://run-ptest \
+    file://CVE-2023-49083.patch \
 "
 
 require ${BPN}-crates.inc