Improper Validation of Unsafe Equivalence in Input Affecting rubygem-loofah package, versions *


Severity

Recommended
0.0
low
0
10

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.39% (31st percentile)

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  • Snyk IDSNYK-RHEL10-RUBYGEMLOOFAH-18948728
  • published19 Aug 2026
  • disclosed12 Aug 2026

Introduced: 12 Aug 2026

CVE-2026-73491  (opens in a new tab)
CWE-1289  (opens in a new tab)

How to fix?

There is no fixed version for RHEL:10 rubygem-loofah.

NVD Description

Note: Versions mentioned in the description apply only to the upstream rubygem-loofah package and not the rubygem-loofah package as distributed by RHEL. See How to fix? for RHEL:10 relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1