CVE-2026-73491
Loofah `allowed_uri?` does not detect `javascript:` URIs split by named whitespace character references
- State
- Published
- Severity
- 2.3 Low
- Published
- Aug 12, 2026
- Updated
- Aug 13, 2026
- Reserved
- Aug 12, 2026
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: URIs whose scheme is split or prefixed with the HTML5 named whitespace character references 	 or 
. CGI.unescapeHTML leaves those references intact, so allowed_uri? reports the URL safe even though a browser decodes and strips the tab or line feed and executes the resulting javascript: URL. 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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 2.3 Low | CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N | GitHub_M |
Weaknesses
- CWE-184 Incomplete List of Disallowed Inputs
Affected Products
| Product | Versions |
|---|---|
loofahflavorjones |
|
References
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