CVE-2023-49083: cryptography vulnerable to NULL-dereference when loading PKCS7 certificates
Summary
Calling loadpempkcs7certificates or loadderpkcs7certificates could lead to a NULL-pointer dereference and segfault.
PoC Here is a Python code that triggers the issue: python from cryptography.hazmat.primitives.serialization.pkcs7 import loadderpkcs7certificates, loadpempkcs7certificates
pemp7 = b""" -----BEGIN PKCS7----- MAsGCSqGSIb3DQEHAg== -----END PKCS7----- """
derp7 = b"\x30\x0B\x06\x09\x2A\x86\x48\x86\xF7\x0D\x01\x07\x02"
loadpempkcs7certificates(pemp7) loadderpkcs7certificates(derp7)
Impact 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.
Other sources
cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. Calling loadpempkcs7certificates or loadderpkcs7certificates 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.
— Ubuntu
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
pip/cryptographyto a version that resolves this vulnerability.Fixed in 41.0.6 - Upgrade
Upgrade
debian/python-cryptographyto a version that resolves this vulnerability.Fixed in 2.6.1-3+deb10u2Fixed in 2.6.1-3+deb10u4 - Upgrade
Upgrade
ubuntu/python-cryptographyto a version that resolves this vulnerability.Fixed in 3.4.8-1ubuntu2.1 - Upgrade
Upgrade
ubuntu/python-cryptographyto a version that resolves this vulnerability.Fixed in 38.0.4-2ubuntu0.1 - Upgrade
Upgrade
ubuntu/python-cryptographyto a version that resolves this vulnerability.Fixed in 38.0.4-4ubuntu0.23.10.1 - Upgrade
Upgrade
redhat/python-cryptographyto a version that resolves this vulnerability.Fixed in 41.0.6 - Upgrade
Upgrade
cryptographyto a version that resolves this vulnerability.Fixed in 41.0.6Patch CVE-2023-49083
Event History
Frequently Asked Questions
What is the vulnerability ID of this issue?
The vulnerability ID of this issue is CVE-2023-49083.
What is the summary of this vulnerability?
Calling `load_pem_pkcs7_certificates` or `load_der_pkcs7_certificates` could lead to a NULL-pointer dereference and segfault.
How can this vulnerability be triggered?
This vulnerability can be triggered by calling `load_pem_pkcs7_certificates` or `load_der_pkcs7_certificates`.
What is the affected software?
The affected software is cryptography version 3.1 up to and including 41.0.6.
Where can I find more information about this vulnerability?
You can find more information about this vulnerability in the following references: [GitHub Advisory GHSA-jfhm-5ghh-2f97](https://github.com/pyca/cryptography/security/advisories/GHSA-jfhm-5ghh-2f97), [GitHub Commit f09c261ca10a31fe41b1262306db7f8f1da0e48a](https://github.com/pyca/cryptography/commit/f09c261ca10a31fe41b1262306db7f8f1da0e48a), [GitHub Advisory GHSA-jfhm-5ghh-2f97](https://github.com/advisories/GHSA-jfhm-5ghh-2f97).