CVE-2026-39823

Bypass of meta content URL escaping causes XSS in html/template

Medium · published May 7, 2026

CVSS v3.1
6.1
EPSS
0%
Percentile
25.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.1 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00333 · 25.2th percentile
Published
2026-05-07T19:41Z
EPSS history
Timeline
  • 07 MAY 19:41Z
    Bypass of meta content URL escaping causes XSS in html/template
    cvelistv5