CVE-2026-27136medium

CVE-2026-27136: medium-severity vulnerability in golang.org/x/net/html

Invoking duplicate attributes can cause XSS in golang.org/x/net/html

Published

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.1epss 0.2%
Parsing arbitrary HTML which is then rendered using Render can result in an unexpected HTML tree. This can be leveraged to execute XSS attacks in applications that attempt to sanitize input HTML before rendering.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Affected products
golang.org/x/net · golang.org/x/net/html
Related CVEs — golang.org/x/net/html

In the same product, most dangerous first.

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