CVE-2018-3741

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-03-30 · updated 2026-06-17
Weakness: CWE-79

Description

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: through 1.0.3

References

https://github.com/rails/rails-html-sanitizer/commit/f3ba1a839a35f2ba7f941c15e239a1cb379d56ae
https://github.com/rails/rails-html-sanitizer/commit/f3ba1a839a35f2ba7f941c15e239a1cb379d56ae

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