CVE-2023-50782: Python-cryptography: bleichenbacher timing oracle attack against rsa decryption - incomplete fix for cve-2020-25659

Published Dec 13, 2023
·
Updated

A flaw was found in the python-cryptography package. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Other sources

Description: The fix for CVE-2020-25659 is not addressing the leakage in the RSA decryption. Because of the API design, the fix is generally not believed to be possible to be fully addressed. The issue can be mitigated by using a cryptographic backed that implements implicit rejection (Marvin workaround). Only applications that use RSA decryption with PKCS#1 v1.5 padding are affected.

Implicit rejection in RHEL has shipped in 9.3.0. Will ship in 9.2.eus, 8.6.eus, 8.8.eus, and 8.9.z. No other releases are planned

References: https://github.com/pyca/cryptography/issues/9785 https://people.redhat.com/~hkario/marvin/ https://github.com/openssl/openssl/pull/13817

Red Hat

Affected Software

11 affected componentsFixes available
pip/cryptography<42.0.0
42.0.0
debian/python-cryptography<=3.3.2-1, <=3.3.2-1+deb11u1, <=38.0.4-3+deb12u1, <=38.0.4-3~deb12u1
43.0.0-1
redhat Ansible Automation Platform=2.0
redhat Enterprise Linux=8.0
redhat Enterprise Linux=9.0
redhat Update Infrastructure=4
Cryptography.io Cryptography Python<42.0.0
Couchbase Couchbase Server=7.6.0
Couchbase Couchbase Server=7.6.1
redhat/cryptography<42.0.0
42.0.0
IBM Edge Application Manager<=4.5

Event History

Dec 13, 2023
Data Sourced
via Red Hat·09:45 PM
DescriptionSeverityAffected Software
Feb 5, 2024
CVE Published
via MITRE·08:45 PM
Data Sourced
via MITRE·08:45 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·09:15 PM
DescriptionSeverityWeaknessAffected Software
Advisory Published
via GitHub·09:30 PM
Mar 4, 2024
Data Sourced
via Launchpad·03:30 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·03:57 PM
RemedyDescriptionSeverityAffected Software
Aug 20, 2025
Data Sourced
via IBM·12:00 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2023-50782?

CVE-2023-50782 is considered a critical vulnerability due to the potential exposure of confidential data.

2

How do I fix CVE-2023-50782?

To fix CVE-2023-50782, upgrade the python-cryptography package to version 42.0.0 or higher.

3

Which systems are affected by CVE-2023-50782?

CVE-2023-50782 affects versions of the python-cryptography package below 42.0.0.

4

Can CVE-2023-50782 lead to data breaches?

Yes, CVE-2023-50782 could allow remote attackers to decrypt messages leading to potential data breaches.

5

What is the nature of the vulnerability in CVE-2023-50782?

The vulnerability in CVE-2023-50782 arises from inadequate protection of RSA key exchanges in TLS servers.

Contact

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