Vulnerability · Published May 26, 2026 · Assigned by GitHub_M
CVE-2026-44837view_component: System Test Entry Point Path Check Allows Sibling Directory Escape
Medium 5.9
In plain English
A medium-severity security flaw in view_component from ViewComponent. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 36% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
view_component is a framework for building reusable, testable, and encapsulated view components in Ruby on Rails. From 3.0.0 to 4.9.0, 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. This vulnerability is fixed in 4.9.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | ruby-view-component | no fix listed | DEBIAN-CVE-2026-44837 |
| Debian:14 | ruby-view-component | 4.12.0-1 | DEBIAN-CVE-2026-44837 |
| RubyGems | view_component | 4.9.0 | GHSA-hg3h-g7xc-f7vp |
| Ubuntu:24.04:LTS | ruby-view-component | no fix listed | UBUNTU-CVE-2026-44837 |
| Ubuntu:26.10 | ruby-view-component | no fix listed | UBUNTU-CVE-2026-44837 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| ViewComponent | view_component | >= 3.0.0, < 4.9.0 |
Weakness: CWE-187 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N