CVE-2026-73648: Rails HTML Sanitizers: Possible XSS vulnerability with certain configurations

CVE-2026-73648 · Severity: medium · CVSS 4 · Published 2026-08-13

rails-html-sanitizer is responsible for sanitizing HTML fragments in Rails applications. From 1.0.3 until 1.7.1, Rails::HTML::PermitScrubber restricted SVG reference elements in SVG_ALLOW_LOCAL_HREF only when they used xlink:href, even though browsers also accept the plain href attribute. Applications with non-default allowed tags that included SVG use or feImage elements could therefore permit external references; a same-origin external SVG referenced by use could execute scripts in the sanitized document's context, while feImage could load external images for tracking. Applications using the default allowed tags are not affected. This issue is fixed in version 1.7.1.

Technologies: rails-html-sanitizer (RubyGems). Vendors: RubyGems.

Quick answers

Is CVE-2026-73648 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-73648 being exploited in the wild.
How severe is CVE-2026-73648?
Medium severity, with a CVSS score of 4, published 13 August 2026.
Which products and versions are affected?
rails-html-sanitizer (RubyGems) ECOSYSTEM:introduced=1.0.3,fixed=1.7.1.
Is there a fix for CVE-2026-73648?
Yes. rails-html-sanitizer (RubyGems): upgrade to 1.7.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2026-73648?
Check whether you run rails-html-sanitizer (RubyGems) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • rails-html-sanitizer (RubyGems): upgrade to 1.7.1 or later
    bundle update rails-html-sanitizer

Affected products

  • rails-html-sanitizer (RubyGems) ECOSYSTEM:introduced=1.0.3,fixed=1.7.1

Identifiers

  • CVE-2026-73648
  • GHSA-cj75-f6xr-r4g7

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