CVE-2018-3741: Rubyonrails Html Sanitizer

Medium severity, CVSS 6.1. EPSS: 1.3% chance of exploitation in the next 30 days.

There is a possible XSS vulnerability in all rails-html-sanitizer gem versions below 1.0.4 for Ruby. The gem allows non-whitelisted attributes to be present in sanitized output when input with specially-crafted HTML fragments, and these attributes can lead to an XSS attack on target applications. This issue is similar to CVE-2018-8048 in Loofah. All users running an affected release should either upgrade or use one of the workarounds immediately.

Affected products

• Rubyonrails Html Sanitizer: up to and including 1.0.3

Published 2018-03-30. Last modified 2026-06-17.