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Vulnerability record/PUBLISHED/Published Aug 31, 2026 08:47:51 UTC

CVE-2026-81624

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.

Base score7.5/ 10
SeverityHighCVSS 3.1

Exploitability / impact

CVSS metric breakdown

Vector-derived attributes
Base severityHigh
Attack vectorNetworkAV
Attack complexityLowAC
Privileges requiredNonePR
User interactionNoneUI
ScopeUnchangedS
Confidentiality impactNoneC
Integrity impactNoneI
Availability impactHighA
CVSS vector stringCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS communicates standardized severity and impact characteristics. It does not establish whether a system is exploitable in your specific environment.

Record context

CVE Numbering Authorityredhat
Last updatedNov 4, 2026 23:43:12 UTC
PublishedAug 31, 2026 08:47:51 UTC
ReservedAug 27, 2026 08:40:49 UTC