Bug 2514986 (CVE-2026-73491) - CVE-2026-73491 rubygem-loofah: Loofah: Cross-Site Scripting via malformed `javascript:` URI parsing
Summary: CVE-2026-73491 rubygem-loofah: Loofah: Cross-Site Scripting via malformed `ja...
Keywords:
Status: NEW
Alias: CVE-2026-73491
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
low
low
Target Milestone: ---
Assignee: Product Security
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-08-12 21:01 UTC by OSIDB Bzimport
Modified: 2026-08-20 14:32 UTC (History)
23 users (show)

Fixed In Version:
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Description OSIDB Bzimport 2026-08-12 21:01:26 UTC 
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.
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