CVE Vulnerabilities

CVE-2026-34785

Partial String Comparison

Published: Apr 02, 2026 | Modified: Apr 16, 2026
CVSS 3.x
N/A
Source:
NVD
CVSS 2.x
RedHat/V2
RedHat/V3
7.5 IMPORTANT
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Ubuntu
MEDIUM
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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.

Weakness

The product performs a comparison that only examines a portion of a factor before determining whether there is a match, such as a substring, leading to resultant weaknesses.

Affected Software

NameVendorStart VersionEnd Version
RackRack*2.2.23 (excluding)
RackRack3.0.0 (including)3.1.21 (excluding)
RackRack3.2.0 (including)3.2.6 (excluding)
Ruby-rackUbuntudevel*
Ruby-rackUbuntuesm-apps-legacy/xenial*
Ruby-rackUbuntuesm-apps/bionic*
Ruby-rackUbuntuesm-apps/focal*
Ruby-rackUbuntuesm-apps/jammy*
Ruby-rackUbuntuesm-apps/xenial*
Ruby-rackUbuntuesm-infra-legacy/trusty*
Ruby-rackUbuntujammy*
Ruby-rackUbuntunoble*
Ruby-rackUbuntuquesting*
Ruby-rackUbunturesolute*

Potential Mitigations

References