CVE-2026-73492
Loofah `allowed_uri?` does not detect `javascript:` URIs split by numeric character references without semicolons
Record summary
CVE-2026-73492 has a selected CVSS score of 2.3 (low).
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 2.25.2, Loofah::HTML5::Scrub.allowed_uri? does not reject javascript: or vbscript: URIs whose scheme is split by semicolon-less numeric character references such as :, 	, 
, or 
. CGI.unescapeHTML leaves these references encoded, so allowed_uri? reports the URL safe even though a browser decodes an encoded colon or strips encoded whitespace and executes the resulting URI scheme. This issue affects only callers that pass HTML-encoded strings directly to allowed_uri?; Loofah's default sanitize() path is not affected. This issue is fixed in version 2.25.2.
Affected products and versions
1| Product | Source | Version range | Status |
|---|---|---|---|
| CVE List | >= 2.25.0, < 2.25.2 | affected |