CVE-2026-39823
Bypass of meta content URL escaping causes XSS in html/template
6.1
MEDIUM
CVSS 3.1
EPSS 0.01%
Description
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.
How to fix CVE-2026-39823
To remediate CVE-2026-39823, upgrade the affected package to a fixed version below.
- —upgrade to 1.25.10 or later
- —no fix listed
- —no fix listed
- —no fix listed
- —upgrade to 1.25.10-1 or later
- —upgrade to 1.26.3-1 or later
- —upgrade to 1.25.10 or later
Is CVE-2026-39823 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (7)
- from 0, < 1.25.10, >= 1.26.0-0, < 1.26.3
- from 0
- from 0
- from 0
- from 0, < 1.25.10-1
- from 0, < 1.26.3-1
- from 0, < 1.25.10, >= 1.26.0-0, < 1.26.3
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |