CVE-2026-81624
Undertow-core: undertow: websocketcontainer defaults for buffers and timeouts are infinite
Undertow is a flexible performant web server used in JBoss EAP and WildFly. A flaw was found in how Undertow handles WebSocket connections. Specifically, certain configuration limits like message buffer sizes and session timeouts cannot be adjusted and default to being unlimited. This allows a remote attacker to send large amounts of data or maintain connections indefinitely, potentially crashing the server by exhausting its memory or other resources.
Fixes and workarounds
Workaround
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Source: CNA: redhatAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| Red Hat build of Apache Camel for Spring Boot 4 Red Hat undertow-core
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 10 Red Hat moditect
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat Enterprise Linux 8 Red Hat pki-core:10.6/resteasy
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat Enterprise Linux 8 Red Hat pki-deps:10.6/resteasy
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat Enterprise Linux 9 Red Hat resteasy
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat Fuse 7 Red Hat undertow-core
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat JBoss Enterprise Application Platform 7 Red Hat jboss-eap-7/eap74-els-openjdk11-openshift-rhel8
https://access.redhat.com/jbossnetwork/restricted/listSoftware.html |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat JBoss Enterprise Application Platform 7 Red Hat jboss-eap-7/eap74-els-openjdk17-openshift-rhel8
https://access.redhat.com/jbossnetwork/restricted/listSoftware.html |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat JBoss Enterprise Application Platform 7 Red Hat jboss-eap-7/eap74-els-openjdk8-openshift-rhel8
https://access.redhat.com/jbossnetwork/restricted/listSoftware.html |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat JBoss Enterprise Application Platform 7 Red Hat undertow-core
https://access.redhat.com/jbossnetwork/restricted/listSoftware.html |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat JBoss Enterprise Application Platform 8 Red Hat undertow-core
https://access.redhat.com/jbossnetwork/restricted/listSoftware.html |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat JBoss Enterprise Application Platform Expansion Pack Red Hat undertow-core
https://access.redhat.com/jbossnetwork/restricted/listSoftware.html |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat Single Sign-On 7 Red Hat undertow-core
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA: redhat |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://access.redhat.com/security/cve/CVE-2026-81624CNA: redhat · vdb-entry, x_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2524868CNA: redhat · issue-tracking, x_refsource_REDHAT
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