What is CVE-2026-39823?

CVE-2026-39823 is a medium-severity vulnerability in Golang Go, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-05-07.

How severe is CVE-2026-39823?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Golang Go

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 esca…

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.000 (1.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

Golang Go
Go Standard Library Html/template — versions 0, 1.26.0-0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

security@golang.org (Issue Tracking)
security@golang.org (Patch)
security@golang.org (Release Notes)
security@golang.org (Vendor Advisory)

Frequently asked questions

What is CVE-2026-39823?: CVE-2026-39823 is a medium-severity vulnerability in Golang Go, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-05-07.
How severe is CVE-2026-39823?: Medium severity. CVSS v3 base score is 6.1 out of 10.