HTTP Request Smuggling Affecting undertow package, versions *


Severity

Recommended
0.0
critical
0
10

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Threat Intelligence

EPSS
0.71% (49th percentile)

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  • Snyk IDSNYK-DEBIANUNSTABLE-UNDERTOW-15805884
  • published29 Mar 2026
  • disclosed27 Mar 2026

Introduced: 27 Mar 2026

CVE-2026-28367  (opens in a new tab)
CWE-444  (opens in a new tab)

How to fix?

There is no fixed version for Debian:unstable undertow.

NVD Description

Note: Versions mentioned in the description apply only to the upstream undertow package and not the undertow package as distributed by Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1