CVE-2026-56858 - Vulnerability Details - OpenCVE

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

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.

The EPSS score is 0.00199.

Exploitation none

Automatable no

Technical Impact partial

Vendors	Products
Go Standard Library	Html/template

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	Html/template

References

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

History

Fri, 14 Aug 2026 16:30:00 +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, 14 Aug 2026 01:30:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-79

Thu, 13 Aug 2026 23:45:00 +0000

Type	Values Removed	Values Added
First Time appeared		Go Standard Library Go Standard Library html/template
Vendors & Products		Go Standard Library Go Standard Library html/template

Thu, 13 Aug 2026 22:15:00 +0000

Type	Values Removed	Values Added
Description		Previously, pathological inputs could close an unescaped '/' early, allowing for attack-controlled data to inject arbitrary content, potentially leading to XSS.
Title		Fix Javascript regexp context tracking in html/template
References		https://go.dev/cl/807100 https://go.dev/issue/80435 https://groups.google.com/g/golang-announce/c/94pEornpRlI https://pkg.go.dev/vuln/GO-2026-6091

MITRE

Status: PUBLISHED

Assigner: Go

Published: 2026-08-13T21:58:53.354Z

Updated: 2026-08-14T15:32:29.852Z

Reserved: 2026-06-23T15:10:49.353Z

Link: CVE-2026-56858

Vulnrichment

Updated: 2026-08-14T15:32:20.906Z

NVD

Status : Received

Published: 2026-08-13T22:17:22.207

Modified: 2026-08-14T16:16:57.367

Link: CVE-2026-56858

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-08-14T01:15:17Z

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