CVE-2026-39823

CVE-2026-27142 fixed a vulnerability in which URLs were not correctly escaped inside of a <meta> tag's <content> attribute. If the URL content were to insert ASCII whitespaces around the '=' rune inside of the <content> attribute, the escaper would fail to similarly escape it, leading to XSS.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://go.dev/cl/769920	Patch
https://go.dev/issue/78913	Issue Tracking
https://groups.google.com/g/golang-announce/c/qcCIEXso47M	Release Notes
https://pkg.go.dev/vuln/GO-2026-4982	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:golang:go::::::::
	cpe:2.3:a:golang:go::::::::

History

26 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) CVE-2026-27142 corrigió una vulnerabilidad en la que las URL no se escapaban correctamente dentro del atributo [content] de una etiqueta [meta]. Si el contenido de la URL insertara espacios en blanco ASCII alrededor del carácter ’=’ dentro del atributo [content], el mecanismo de escape no lograría escaparlo de manera similar, lo que llevaría a XSS.

Information

Published : 2026-05-07 20:16

Updated : 2026-10-26 20:10

NVD link : CVE-2026-39823

Mitre link : CVE-2026-39823

CVE.ORG link : CVE-2026-39823

JSON object : View

Products Affected

golang

go

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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