CVE-2026-42505

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.

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 LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://go.dev/cl/775960	Patch
https://go.dev/issue/79282	Issue Tracking Patch
https://groups.google.com/g/golang-announce/c/OrmQE_Yp5Sc	Mailing List Release Notes Vendor Advisory
https://pkg.go.dev/vuln/GO-2026-5856	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:golang:go::::::::
	cpe:2.3:a:golang:go::::::::
	cpe:2.3:a:golang:go:1.27:rc1::::::

History

13 Jul 2026, 17:05

Type	Values Removed	Values Added
References	~~() https://go.dev/cl/775960 -~~	() https://go.dev/cl/775960 - Patch
References	~~() https://go.dev/issue/79282 -~~	() https://go.dev/issue/79282 - Issue Tracking, Patch
References	~~() https://groups.google.com/g/golang-announce/c/OrmQE_Yp5Sc -~~	() https://groups.google.com/g/golang-announce/c/OrmQE_Yp5Sc - Mailing List, Release Notes, Vendor Advisory
References	~~() https://pkg.go.dev/vuln/GO-2026-5856 -~~	() https://pkg.go.dev/vuln/GO-2026-5856 - Vendor Advisory
CPE		cpe:2.3:a:golang:go:::::::: cpe:2.3:a:golang:go:1.27:rc1::::::
First Time		Golang Golang go

08 Jul 2026, 20:16

Type	Values Removed	Values Added
CWE		CWE-201
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.3

08 Jul 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-08 17:17

Updated : 2026-07-13 17:05

NVD link : CVE-2026-42505

Mitre link : CVE-2026-42505

CVE.ORG link : CVE-2026-42505

JSON object : View

Products Affected

golang

go

CWE

CWE-201

Insertion of Sensitive Information Into Sent Data

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