Medium 6.1Published Aug 13, 2026

CVE-2026-56858Fix Javascript regexp context tracking in html/template

Updated under an hour ago (Oct 27, 2026, 6:50 PM ET)

Does this affect you?

It affects Go standard library html/template. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for Go standard library html/template

Exploited in the last 30 days

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

CVSS: 6.1 MEDIUM (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness (CWE): CWE-79
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Go
NVD analysis: Awaiting Analysis
Record last updated: Aug 14, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Go standard library html/template go_standard_library:html_template (from the name)	before 1.25.13; from 1.26.0-0 before 1.26.6; 1.27.0-0 builds before 1.27.0-rc.3	CNA record

References

References

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

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.