CVE-2026-34826
Publication date 2 April 2026
Last updated 23 April 2026
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| ruby-rack | 25.10 questing |
Fixed 3.1.16-0.1ubuntu0.3
|
| 24.04 LTS noble |
Fixed 2.2.7-1ubuntu0.7
|
|
| 22.04 LTS jammy |
Fixed 2.1.4-5ubuntu1.2+esm3
|
|
| 20.04 LTS focal |
Fixed 2.0.7-2ubuntu0.1+esm10
|
|
| 18.04 LTS bionic |
Fixed 1.6.4-4ubuntu0.2+esm10
|
|
| 16.04 LTS xenial |
Fixed 1.6.4-3ubuntu0.2+esm10
|
|
| 14.04 LTS trusty | Ignored changes too intrusive |
Get expanded security coverage with Ubuntu Pro
Reduce your average CVE exposure time from 98 days to 1 day with expanded CVE patching, ten-years security maintenance and optional support for the full stack of open-source applications. Free for personal use.
Get Ubuntu Pro 30-day free trialSeverity score breakdown
| Parameter | Value |
|---|---|
| Base score |
5.3 · Medium
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity impact | None |
| Availability impact | Low |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
References
Related Ubuntu Security Notices (USN)
- USN-8182-1
- Rack vulnerabilities
- 17 April 2026