CVE-2026-34826

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Utils.get_byte_ranges parses the HTTP Range header without limiting the number of individual byte ranges. Although the existing fix for CVE-2024-26141 rejects ranges whose total byte coverage exceeds the file size, it does not restrict the count of ranges. An attacker can supply many small overlapping ranges such as 0-0,0-0,0-0,... to trigger disproportionate CPU, memory, I/O, and bandwidth consumption per request. This results in a denial of service condition in Rack file-serving paths that process multipart byte range responses. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/rack/rack/security/advisories/GHSA-x8cg-fq8g-mxfx	Vendor Advisory Mitigation

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

16 Apr 2026, 17:09

Type	Values Removed	Values Added
References	~~() https://github.com/rack/rack/security/advisories/GHSA-x8cg-fq8g-mxfx -~~	() https://github.com/rack/rack/security/advisories/GHSA-x8cg-fq8g-mxfx - Vendor Advisory, Mitigation
CPE		cpe:2.3:a:rack:rack::::::ruby::*
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 : 2026-04-16 17:09

NVD link : CVE-2026-34826

Mitre link : CVE-2026-34826

CVE.ORG link : CVE-2026-34826

JSON object : View

Products Affected

rack

rack

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-770

Allocation of Resources Without Limits or Throttling

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