CVE-2026-34785 (GCVE-0-2026-34785)

Vulnerability from cvelistv5 – Published: 2026-04-02 16:44 – Updated: 2026-06-30 12:09
VLAI
Title
Rack: Local file inclusion in `Rack::Static` via URL Prefix Matching
Summary
Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Static determines whether a request should be served as a static file using a simple string prefix check. When configured with URL prefixes such as "/css", it matches any request path that begins with that string, including unrelated paths such as "/css-config.env" or "/css-backup.sql". As a result, files under the static root whose names merely share the configured prefix may be served unintentionally, leading to information disclosure. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-187 - Partial String Comparison
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-552 - Files or Directories Accessible to External Parties
Assigner
References
Impacted products
Vendor Product Version
rack rack Affected: < 2.2.23
Affected: >= 3.0.0.beta1, < 3.1.21
Affected: >= 3.2.0, < 3.2.6
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Red Hat Red Hat Satellite 6     cpe:/a:redhat:satellite:6
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