CVE-2026-34826

Public on 2026-04-02
Modified on 2026-04-03
Description
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.
Severity
Medium severity
Medium
See what this means
CVSS v3 Base Score
5.3
See breakdown

Affected Packages

Platform Package Release Date Advisory Status
Amazon Linux 2 - Core pcs Not Affected

CVSS Scores

Score Type Score Vector
Amazon Linux CVSSv3 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L