CVE-2026-39823 (GCVE-0-2026-39823)

Vulnerability from cvelistv5 – Published: 2026-05-07 19:41 – Updated: 2026-05-08 14:05
VLAI
Title
Bypass of meta content URL escaping causes XSS in html/template
Summary
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.
Severity
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-08 14:05 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version CPE status
Go standard library html/template Affected: 0 , < 1.25.10 (semver)
Affected: 1.26.0-0 , < 1.26.3 (semver)
guessed Create a notification for this product.
Credits
Samy Ghannad
Show details on NVD website
To clipboard 

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