CVE-2026-126206

Name	CVE-2026-126206
Description	Loofah is a general library for manipulating and transforming HTML/XML documents and fragments, built on top of Nokogiri. In 2.25.2, Loofah::HTML5::Scrub.allowed_uri? treats a data URI mediatype containing the HTML5 named solidus reference / as malformed and falls back to the allowed text/plain, while a browser decodes the reference and interprets the same value as text/html. An application that validates a user-controlled URL with this helper and renders the approved value in href or another browser-interpreted URI attribute can allow cross-site scripting. Rails::HTML::Sanitizer.allowed_uri? re-exports the affected helper. Loofah's default sanitize() path is not affected because Nokogiri decodes the entity before URI validation. This issue is fixed in version 2.25.3.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
ruby-loofah (PTS)	bookworm	2.19.1-1	vulnerable
	trixie	2.24.0-1	vulnerable
	forky	2.25.2-1	vulnerable
	sid	2.25.3-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
ruby-loofah	source	(unstable)	2.25.3-1

Notes

https://github.com/flavorjones/loofah/security/advisories/GHSA-jcff-cj73-4w4f
https://github.com/flavorjones/loofah/pull/324
https://github.com/flavorjones/loofah/commit/ad92002966053309f83b550861e2ef04bc714744 (v2.25.3)