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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.

PUBLISHED Reserved 2026-02-27 | Published 2026-03-27 | Updated 2026-04-10 | Assigner redhat




HIGH: 8.7CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

Problem types

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

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Timeline

2026-02-27:Reported to Red Hat.
2025-08-27:Made public.

References

access.redhat.com/security/cve/CVE-2026-28367 vdb-entry

bugzilla.redhat.com/show_bug.cgi?id=2443260 (RHBZ#2443260) issue-tracking

cve.org (CVE-2026-28367)

nvd.nist.gov (CVE-2026-28367)

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