CVE-2026-34785

HIGH

Rack: Local file inclusion in `Rack::Static` via URL Prefix Matching

Title source: cna
STIX 2.1

Description

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.

Scores

CVSS v3 7.5
EPSS 0.0004
EPSS Percentile 12.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-187 CWE-200
Status published
Products (4)
rack/rack < 2.2.23 (2 CPE variants)
rack/rack >= 3.0.0.beta1, < 3.1.21
rack/rack >= 3.2.0, < 3.2.6
rubygems/rack 0 - 2.2.23RubyGems
Published Apr 02, 2026
Tracked Since Apr 02, 2026