CVE-2026-27142 (GCVE-0-2026-27142)

Vulnerability from cvelistv5 – Published: 2026-03-06 21:28 – Updated: 2026-03-16 15:21
VLAI
Title
URLs in meta content attribute actions are not escaped in html/template
Summary
Actions which insert URLs into the content attribute of HTML meta tags are not escaped. This can allow XSS if the meta tag also has an http-equiv attribute with the value "refresh". A new GODEBUG setting has been added, htmlmetacontenturlescape, which can be used to disable escaping URLs in actions in the meta content attribute which follow "url=" by setting htmlmetacontenturlescape=0.
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 2026-03-16 15:21 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
Go standard library html/template Affected: 0 , < 1.25.8 (semver)
Affected: 1.26.0-0 , < 1.26.1 (semver)
Create a notification for this product.
Show details on NVD website
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          },
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            "value": "Acciones que insertan URLs en el atributo content de las etiquetas meta HTML no se escapan. Esto puede permitir XSS si la etiqueta meta tambi\u00e9n tiene un atributo http-equiv con el valor \u0027refresh\u0027. Se ha a\u00f1adido una nueva configuraci\u00f3n GODEBUG, htmlmetacontenturlescape, que se puede usar para deshabilitar el escape de URLs en acciones en el atributo content de las etiquetas meta que siguen a \u0027url=\u0027 al establecer htmlmetacontenturlescape=0."
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