CVE-2026-42505 - Vulnerability Details - OpenCVE

Handshakes which used Encrypted Client Hello could be de-anonymized by a passive network observer due to a disclosure of pre-shared key identities in the unencrypted client hello.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable yes

Technical Impact partial

Vendors	Products
Go Standard Library	Crypto Tls

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors	Products
Go Standard Library	Crypto Tls

References

Link	Providers
https://go.dev/cl/775960
https://go.dev/issue/79282
https://groups.google.com/g/golang-announce/c/OrmQE_Yp5Sc
https://pkg.go.dev/vuln/GO-2026-5856

History

Wed, 08 Jul 2026 20:30:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-201
Metrics		cvssV3_1 `{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}` ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Wed, 08 Jul 2026 18:30:00 +0000

Type	Values Removed	Values Added
First Time appeared		Go Standard Library Go Standard Library crypto Tls
Vendors & Products		Go Standard Library Go Standard Library crypto Tls

Wed, 08 Jul 2026 16:30:00 +0000

Type	Values Removed	Values Added
Description		Handshakes which used Encrypted Client Hello could be de-anonymized by a passive network observer due to a disclosure of pre-shared key identities in the unencrypted client hello.
Title		Invoking Encrypted Client Hello privacy leak in crypto/tls
References		https://go.dev/cl/775960 https://go.dev/issue/79282 https://groups.google.com/g/golang-announce/c/OrmQE_Yp5Sc https://pkg.go.dev/vuln/GO-2026-5856

MITRE

Status: PUBLISHED

Assigner: Go

Published: 2026-07-08T15:46:33.407Z

Updated: 2026-07-08T19:38:17.603Z

Reserved: 2026-04-28T00:21:12.792Z

Link: CVE-2026-42505

Vulnrichment

Updated: 2026-07-08T18:04:08.858Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-07-08T18:15:06Z

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