CVE-2026-34073

cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. Prior to version 46.0.6, DNS name constraints were only validated against SANs within child certificates, and not the "peer name" presented during each validation. Consequently, cryptography would allow a peer named bar.example.com to validate against a wildcard leaf certificate for *.example.com, even if the leaf's parent certificate (or upwards) contained an excluded subtree constraint for bar.example.com. This issue has been patched in version 46.0.6.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/pyca/cryptography/security/advisories/GHSA-m959-cc7f-wv43	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:cryptography.io:cryptography:*:*:*:*:*:python:*:*

History

No history.

Information

Published : 2026-03-31 03:15

Updated : 2026-06-17 10:38

NVD link : CVE-2026-34073

Mitre link : CVE-2026-34073

CVE.ORG link : CVE-2026-34073

JSON object : View

Products Affected

cryptography.io

cryptography

CWE

CWE-295

Improper Certificate Validation

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