CVE-2026-28367
Publication date 27 March 2026
Last updated 1 April 2026
Ubuntu priority
Description
A flaw was found in Undertow. A remote attacker can exploit this vulnerability by sending `\r\r\r` as a header block terminator. This can be used for request smuggling with certain proxy servers, such as older versions of Apache Traffic Server and Google Cloud Classic Application Load Balancer, potentially leading to unauthorized access or manipulation of web requests.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| undertow | 26.04 LTS resolute |
Needs evaluation
|
| 25.10 questing |
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 |
Severity score breakdown
CVSS version: CVSS v3.0
Base score
8.7 · High
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N