Description
view_component is a framework for building reusable, testable, and encapsulated view components in Ruby on Rails. From 4.0.0 until 4.12.0, ViewComponent::Base#around_render can return HTML-unsafe strings that bypass the escaping behavior applied to normal #call return values. This creates an XSS risk when downstream applications use around_render to wrap, replace, instrument, or conditionally return content that includes user-controlled data, and ViewComponent::Collection#render_in can amplify the issue by joining per-item results and marking the entire output html_safe, converting raw unsafe output into an ActiveSupport::SafeBuffer. This issue is fixed in version 4.12.0.
Affected products
viewcomponent: view component
References5
- github.com/ViewComponent/view_component/security/advisories/GHS… ExploitMitigationVendor Advisory
- github.com/ViewComponent/view_component/security/advisories/GHS… ExploitMitigationVendor Advisory
- github.com/ViewComponent/view_component/commit/48e5fd2d602344c7… Patch
- github.com/ViewComponent/view_component/commit/6796b2e89d0bd7b9… Patch
- github.com/ViewComponent/view_component/releases/tag/v4.12.0 ProductRelease Notes
Metrics
- CVSS 3.1
-
8.7
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 40 · as of 14 November 2026
- CWE
- CWE-79
Could this be exploited in your environment?
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