CVE-2026-28367

Publication date 30 March 2026

Last updated 30 March 2026


Ubuntu priority

Cvss 3 Severity Score

8.7 · High

Score breakdown

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 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
Needs evaluation

Severity score breakdown

Parameter Value
Base score 8.7 · High
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Scope Changed
Confidentiality High
Integrity impact High
Availability impact None
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

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