CVE-2026-5680

Undertow-core: undertow: denial of service via websocket permessage-deflate processing

Published: Aug 27, 2026Updated: Sep 22, 2026 Sources: CVE List NVDCWE-770

7.5HIGH

Description

A flaw was found in Undertow. A remote attacker could exploit this vulnerability by sending specially crafted WebSocket messages with permessage-deflate negotiated. This could lead to excessive memory consumption due to the PerMessageDeflateFunction.largerBuffer() method using exponential doubling, resulting in a Denial of Service (DoS) for the affected application.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-770

Affected Products

Red Hat

commercial·US

Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 10On-prem

Operating Systems / linux-distro

Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8On-prem

Operating Systems / linux-distro

Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9On-prem

Operating Systems / linux-distro

Red Hat build of Apache Camel for Spring Boot 4LibraryLibrary

OSS Libraries / generic-library

Red Hat build of Apache Camel - HawtIO 4LibraryLibrary

OSS Libraries / generic-library

Red Hat Data Grid 8On-premDatabase

Databases / cache-message-queue

Red Hat Enterprise Linux 10On-premOS

Operating Systems / linux-distro

Red Hat Fuse 7On-premDev Tool

DevTools & CI / ci-cd

and 6 more affected products View all →

Exploitability

Workaround Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Impact

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References

https://access.redhat.com/errata/RHSA-2026:70228

access.redhat.com

https://access.redhat.com/errata/RHSA-2026:70229

access.redhat.com

https://access.redhat.com/errata/RHSA-2026:70230

access.redhat.com

and 3 more references View all →

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