CVE-2026-56858

MEDIUM6.1Cross-site scripting

Description

Previously, pathological inputs could close an unescaped '/' early, allowing for attack-controlled data to inject arbitrary content, potentially leading to XSS.

CVSS breakdown

CVSS 3.1

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Affected products

Go standard library / html/template0 – 1.25.13
Go standard library / html/template1.26.0-0 – 1.26.6
Go standard library / html/template1.27.0-0 – 1.27.0-rc.3

References

MISChttps://go.dev/issue/80435
MISChttps://go.dev/cl/807100
MISChttps://groups.google.com/g/golang-announce/c/94pEornpRlI
MISChttps://pkg.go.dev/vuln/GO-2026-6091

Updated 16m ago · 8 sources