CVE-2026-34785

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/rack/rack/security/advisories/GHSA-h2jq-g4cq-5ppq	Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-34785
https://bugzilla.redhat.com/show_bug.cgi?id=2454486
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34785.json

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:rack:rack::::::ruby::*
	cpe:2.3:a:rack:rack::::::ruby::*
	cpe:2.3:a:rack:rack::::::ruby::*

History

30 Jun 2026, 03:18

Type	Values Removed	Values Added
CWE		CWE-552
References		() https://access.redhat.com/security/cve/CVE-2026-34785 - () https://bugzilla.redhat.com/show_bug.cgi?id=2454486 - () https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34785.json -

16 Apr 2026, 17:19

Type	Values Removed	Values Added
CPE		cpe:2.3:a:rack:rack::::::ruby::*
References	~~() https://github.com/rack/rack/security/advisories/GHSA-h2jq-g4cq-5ppq -~~	() https://github.com/rack/rack/security/advisories/GHSA-h2jq-g4cq-5ppq - Vendor Advisory
First Time		Rack rack Rack

02 Apr 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-02 17:16

Updated : 2026-07-15 02:20

NVD link : CVE-2026-34785

Mitre link : CVE-2026-34785

CVE.ORG link : CVE-2026-34785

JSON object : View

Products Affected

rack

rack

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

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