CVE-2026-73491

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 &Tab; or &NewLine;. 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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/flavorjones/loofah/commit/5e91af861e3cdab47b91dd0b81f3afdfd13a5e19
https://github.com/flavorjones/loofah/pull/308
https://github.com/flavorjones/loofah/releases/tag/v2.25.2
https://github.com/flavorjones/loofah/security/advisories/GHSA-8whx-365g-h9vv

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-12 21:17

Updated : 2026-09-09 20:58

NVD link : CVE-2026-73491

Mitre link : CVE-2026-73491

CVE.ORG link : CVE-2026-73491

JSON object : View

Products Affected

No product.

CWE

CWE-184

Incomplete List of Disallowed Inputs

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