CVE-2026-42506 - Vulnerability Details - OpenCVE

Parsing arbitrary HTML which is then rendered using Render can result in an unexpected HTML tree. This can be leveraged to execute XSS attacks in applications that attempt to sanitize input HTML before rendering.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Changed

Confidentiality Impact Low

Integrity Impact Low

Availability Impact None

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

No data.

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

References

Link	Providers
https://go.dev/cl/781700
https://go.dev/issue/79571
https://groups.google.com/g/golang-announce/c/iI-mYSI0lu8
https://pkg.go.dev/vuln/GO-2026-5025

History

Fri, 22 May 2026 18:15:00 +0000

Type	Values Removed	Values Added
Metrics		cvssV3_1 `{'score': 6.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'}` ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Fri, 22 May 2026 15:45:00 +0000

Type	Values Removed	Values Added
Description		Parsing arbitrary HTML which is then rendered using Render can result in an unexpected HTML tree. This can be leveraged to execute XSS attacks in applications that attempt to sanitize input HTML before rendering.
Title		Invoking incorrect handling of namespaced elements in foreign content in golang.org/x/net/html
References		https://go.dev/cl/781700 https://go.dev/issue/79571 https://groups.google.com/g/golang-announce/c/iI-mYSI0lu8 https://pkg.go.dev/vuln/GO-2026-5025

MITRE

Status: PUBLISHED

Assigner: Go

Published: 2026-05-22T15:01:21.056Z

Updated: 2026-05-22T17:45:49.989Z

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

Link: CVE-2026-42506

Vulnrichment

Updated: 2026-05-22T17:45:46.046Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-05-22T20:00:13Z

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