view_component: System Test Entry Point Path Check Allows Sibling Directory Escape — CVE-2026-44837

Summary

### Summary The system test entrypoint canonicalizes a user-controlled file path with `File.realpath`, then checks whether the resolved path starts with the temp directory path. This is not a safe containment check because sibling directories can share the same string prefix. Severity: Medium; test-route scoped. Example: ```text Allowed base: /app/tmp/view_components Outside path:…

Product

rubygems: view_component

What to do

General, cautious steps (verify details in the official source):

• Review exposure and plan remediation based on risk and environment.
• Identify affected product versions in your inventory and verify whether you are impacted.
• Apply vendor patches/updates or recommended mitigations as soon as available.
• Read the official advisory for exact affected versions and remediation steps.

Official advisory

• Read the official source
• CVE Record
• NVD

Related advisories