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.
Published: 2026-08-27
Score: 7.5 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

Vendor Workaround

To mitigate this issue, configure the PerMessageDeflateHandshake to limit the maximum decompressed buffer size. This can be achieved by setting the maxDecompressedBufferSize parameter to a reasonable value (e.g., 10 MB) in the PerMessageDeflateHandshake constructor. This action may require a restart of the affected application or service to take effect.

Tracking

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Advisories

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History

Tue, 01 Sep 2026 14:45:00 +0000

Type Values Removed Values Added
First Time appeared Redhat build Of Apache Camel - Hawtio
Redhat build Of Apache Camel For Spring Boot
Redhat data Grid 8
Redhat jboss Enterprise Application Platform Expansion Pack
Redhat process Automation
Redhat quay 3
Redhat single Sign On
Undertow
Undertow undertow-core
Vendors & Products Redhat build Of Apache Camel - Hawtio
Redhat build Of Apache Camel For Spring Boot
Redhat data Grid 8
Redhat jboss Enterprise Application Platform Expansion Pack
Redhat process Automation
Redhat quay 3
Redhat single Sign On
Undertow
Undertow undertow-core

Mon, 31 Aug 2026 19:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Thu, 27 Aug 2026 16:45:00 +0000

Type Values Removed Values Added
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.
Title Undertow-core: undertow: denial of service via websocket permessage-deflate processing
First Time appeared Redhat
Redhat apache Camel Hawtio
Redhat camel Spring Boot
Redhat enterprise Linux
Redhat jboss Data Grid
Redhat jboss Enterprise Application Platform
Redhat jboss Enterprise Bpms Platform
Redhat jboss Fuse
Redhat jbosseapxp
Redhat red Hat Single Sign On
Weaknesses CWE-770
CPEs cpe:/a:redhat:apache_camel_hawtio:4
cpe:/a:redhat:camel_spring_boot:4
cpe:/a:redhat:jboss_data_grid:8
cpe:/a:redhat:jboss_enterprise_application_platform:7
cpe:/a:redhat:jboss_enterprise_application_platform:8
cpe:/a:redhat:jboss_enterprise_bpms_platform:7
cpe:/a:redhat:jboss_fuse:7
cpe:/a:redhat:jbosseapxp
cpe:/a:redhat:red_hat_single_sign_on:7
cpe:/o:redhat:enterprise_linux:10
cpe:/o:redhat:enterprise_linux:8
cpe:/o:redhat:enterprise_linux:9
Vendors & Products Redhat
Redhat apache Camel Hawtio
Redhat camel Spring Boot
Redhat enterprise Linux
Redhat jboss Data Grid
Redhat jboss Enterprise Application Platform
Redhat jboss Enterprise Bpms Platform
Redhat jboss Fuse
Redhat jbosseapxp
Redhat red Hat Single Sign On
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


Subscriptions

Redhat Apache Camel Hawtio Build Of Apache Camel - Hawtio Build Of Apache Camel For Spring Boot Camel Spring Boot Data Grid 8 Enterprise Linux Jboss Data Grid Jboss Enterprise Application Platform Jboss Enterprise Application Platform Expansion Pack Jboss Enterprise Bpms Platform Jboss Fuse Jbosseapxp Process Automation Quay 3 Red Hat Single Sign On Single Sign On
Undertow Undertow-core
cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2026-09-01T17:39:58.529Z

Reserved: 2026-04-06T09:46:16.983Z

Link: CVE-2026-5680

cve-icon Vulnrichment

Updated: 2026-08-31T18:15:09.269Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-08-27T17:18:58.397

Modified: 2026-09-01T18:17:44.203

Link: CVE-2026-5680

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-01T14:22:57Z

Weaknesses