CVE-2026-39823: Golang Go

Medium severity, CVSS 6.1. EPSS: 0.3% chance of exploitation in the next 30 days.

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 escaper would fail to similarly escape it, leading to XSS.

Affected products

• Golang Go: before 1.25.10 (fixed in 1.25.10); from 1.26.0, before 1.26.3 (fixed in 1.26.3)

Published 2026-05-07. Last modified 2026-06-17.