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💎 RubyGems

GHSA-wf2x-8w6j-qw37

MEDIUM

view_component Cross-site Scripting vulnerability

Also known asCVE-2024-21636
Published
Jan 4, 2024
Updated
Feb 16, 2024
Affected
2 pkgs
Patched
2 / 2
Exploits
1 known

EPSS Exploitation Probability

via FIRST.org ↗
0.5%probability of exploitation in next 30 days
Lower Risk39th percentile-0.01%
0.00%0.33%0.67%1.00%0.5%0.5%Dec 25Apr 26Jun 26

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

2 pkgs affected
💎view_component💎view_component

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.

Description

Impact

What kind of vulnerability is it? Who is impacted?

This is an XSS vulnerability that has the potential to impact anyone rendering a component directly from a controller with the view_component gem. Note that only components that define a #call method (i.e. instead of using a sidecar template) are affected. The return value of the #call method is not sanitized and can include user-defined content.

In addition, the return value of the #output_postamble method is not sanitized, which can also lead to XSS issues.

Patches

Has the problem been patched? What versions should users upgrade to?

Versions 3.9.0 has been released and fully mitigates both the #call and the #output_postamble vulnerabilities.

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

Sanitize the return value of #call, eg:

class MyComponent < ApplicationComponent
  def call
    html_escape("<div>#{user_input}</div>")
  end
end

References

Are there any links users can visit to find out more?

https://github.com/ViewComponent/view_component/pull/1950

For more information

If you have any questions or comments about this advisory:

Open an issue in the github/view_component project.

Affected Packages

2 total 2 fixed
EcosystemPackageVulnerable rangeFix
💎RubyGemsview_component3.0.0&&< 3.9.03.9.0
💎RubyGemsview_componentall versions2.83.0
Exploits & PoCs
1

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for view_component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Fix

    Update view_component to 3.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wf2x-8w6j-qw37 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 pinpoints whether GHSA-wf2x-8w6j-qw37 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-wf2x-8w6j-qw37. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Impact _What kind of vulnerability is it? Who is impacted?_ This is an XSS vulnerability that has the potential to impact anyone rendering a component directly from a controller with the view_component gem. Note that only components that define a [`#call` method](https://viewcomponent.org/guide/templates.html#call) (i.e. instead of using a sidecar template) are affected. The return value of the `#call` method is not sanitized and can include user-defined content. In addition, the return value of the [`#output_postamble` method](https://viewcomponent.org/api.html#output_postamble--string)
O3 Security · Impact-Aware SCA

Is GHSA-wf2x-8w6j-qw37 in your dependencies?

O3 detects GHSA-wf2x-8w6j-qw37 across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.