CVE-2026-27142

HIGH7.5

URLs in meta content attribute actions are not escaped in html/template

Published Mar 6, 2026

Modified 3 days ago

Details

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.

References

WEB

https://go.dev/cl/752081

WEB

https://go.dev/issue/77954

WEB

https://groups.google.com/g/golang-announce/c/EdhZqrQ98hk

WEB

https://pkg.go.dev/vuln/GO-2026-4603

ADVISORY

https://www.cve.org/CVERecord?id=CVE-2026-27142

CVSS Analysis