CVE-2026-34785
Rack: Local file inclusion in `Rack::Static` via URL Prefix Matching
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-187 CWE-200 |
| Vendor | rack |
| Product | rack |
| Published | Apr 2, 2026 |
| Last Updated | Apr 2, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
rack / rack
< 2.2.23 >= 3.0.0.beta1, < 3.1.21 >= 3.2.0, < 3.2.6