CVE-2026-126209

Name	CVE-2026-126209
Description	Loofah is a general library for manipulating and transforming HTML/XML documents and fragments, built on top of Nokogiri. From 2.25.0 until 2.25.3, Loofah::HTML5::Scrub.allowed_uri? strips whitespace and control characters before decoding a semicolon-less numeric character reference, changing where the reference ends and hiding a javascript: or vbscript: scheme that a browser reconstructs. The bypass applies to encoded colons and encoded scheme letters when a stripped character terminates the numeric reference. An application that renders the approved value in href or another browser-interpreted URI attribute can allow cross-site scripting, and Rails::HTML::Sanitizer.allowed_uri? re-exports the affected helper. Loofah's default sanitize() path is not affected because Nokogiri decodes entities before URI evaluation. 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-p9wj-w8xq-vjx6
https://github.com/flavorjones/loofah/pull/324
https://github.com/flavorjones/loofah/commit/62c04841e8252a1b5373afcd2b89fb9b8279e317 (v2.25.3)