PT-2026-71345 · Rubygems · Loofah
CVE-2026-73491
·
Published
2026-07-21
·
Updated
2026-08-12
CVSS v4.0
2.3
Low
| Vector | AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Name of the Vulnerable Software and Affected Versions
Loofah versions 2.25.0 through 2.25.1
Description
Loofah is a library for manipulating and transforming HTML/XML documents and fragments. The
allowed uri? function within Loofah::HTML5::Scrub fails to reject javascript: URIs when the scheme is split or prefixed with HTML5 named whitespace character references such as 	 or 
. Because CGI.unescapeHTML does not remove these references, the function incorrectly identifies the URL as safe. A browser, however, decodes and strips these characters, leading to the execution of the javascript: URL. This issue specifically affects callers that pass HTML-encoded strings directly to the allowed uri? function; the default sanitize() path is not affected.Recommendations
Update to version 2.25.2.
Avoid passing HTML-encoded strings directly to the
allowed uri? function.Exploit
Fix
Incomplete List of Disallowed Inputs
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Weakness Enumeration
Related Identifiers
Affected Products
Loofah