{"id":"CVE-2026-126209","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-126209","summary":"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?…","details":"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.","published":"2026-11-12T21:17:22.210","modified":"2026-11-12T21:17:22.210","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":{"url":"https://github.com/flavorjones/loofah/commit/62c04841e8252a1b5373afcd2b89fb9b8279e317","label":"flavorjones/loofah@62c0484"},"references":[{"type":"WEB","url":"https://github.com/flavorjones/loofah/commit/62c04841e8252a1b5373afcd2b89fb9b8279e317"},{"type":"WEB","url":"https://github.com/flavorjones/loofah/pull/324"},{"type":"WEB","url":"https://github.com/flavorjones/loofah/releases/tag/v2.25.3"},{"type":"WEB","url":"https://github.com/flavorjones/loofah/security/advisories/GHSA-p9wj-w8xq-vjx6"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-11-12T21:17:22.210"}}