CVE-2026-73492 (GCVE-0-2026-73492)

Vulnerability from cvelistv5 – Published: 2026-08-12 21:00 – Updated: 2026-08-14 22:18
VLAI
Title
Loofah `allowed_uri?` does not detect `javascript:` URIs split by numeric character references without semicolons
Summary
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: or vbscript: URIs whose scheme is split by semicolon-less numeric character references such as &#58, &#9, &#10, or &#13. CGI.unescapeHTML leaves these references encoded, so allowed_uri? reports the URL safe even though a browser decodes an encoded colon or strips encoded whitespace and executes the resulting URI scheme. 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.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-14 22:17 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  • CWE-184 - Incomplete List of Disallowed Inputs
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7820 records in the last 180 days details
Impacted products
Vendor Product Version CPE status
flavorjones loofah Affected: >= 2.25.0, < 2.25.2
guessed Create a notification for this product.
Show details on NVD website

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