CVE-2026-33174
Publication date 24 March 2026
Last updated 10 July 2026
Ubuntu priority
Description
Active Storage allows users to attach cloud and local files in Rails applications. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, when serving files through Active Storage's proxy delivery mode, the proxy controller loads the entire requested byte range into memory before sending it. A request with a large or unbounded Range header (e.g. `bytes=0-`) could cause the server to allocate memory proportional to the file size, possibly resulting in a DoS vulnerability through memory exhaustion. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| rails | 26.04 LTS resolute |
Needs evaluation
|
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy |
Needs evaluation
|
|
| 20.04 LTS focal |
Needs evaluation
|
|
| 18.04 LTS bionic |
Needs evaluation
|
|
| 16.04 LTS xenial | Ignored end of ESM support, was needs-triage |
Notes
seth-arnold
In Oneiric-Saucy, rails package is just for transition; The rails package contains actual code from vivid onward
Severity score breakdown
CVSS version:
Base score
6.6 · Medium
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
Base score
7.5 · High
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
Other references
- https://www.cve.org/CVERecord?id=CVE-2026-33174
- https://github.com/rails/rails/commit/2cd933c366b777f873d4d590127da2f4a25e4ba5
- https://github.com/rails/rails/commit/42012eaaa88dfc7d0030161b2bc8074a7bbce92a
- https://github.com/rails/rails/commit/8159a9c3de3f27a2bcf2866b8bf9ceb9075e229b
- https://github.com/rails/rails/releases/tag/v7.2.3.1
- https://github.com/rails/rails/releases/tag/v8.0.4.1
- https://github.com/rails/rails/releases/tag/v8.1.2.1
- https://github.com/rails/rails/security/advisories/GHSA-r46p-8f7g-vvvg