Bug 2524868 (CVE-2026-81624)

Summary:	CVE-2026-81624 undertow-core: undertow: WebSocketContainer defaults for buffers and timeouts are infinite
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	anujha, aschwart, asoldano, aszczucz, bbaranow, bmaxwell, boliveir, bstansbe, dlofthou, drichtar, fmariani, gmalinko, istudens, ivassile, iweiss, janstey, jwon, mcarlett, mosmerov, mposolda, msvehla, nwallace, pberan, pdelbell, pesilva, pjindal, pmackay, rhel-process-autobot, rmartinc, rstancel, rstepani, ssilvert, sthorger, tcunning, thjenkin, vdosoudi, vmuzikar, watson-tool-maintainers, yfang
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	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.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2526163, 2526164
Bug Blocks:

Description OSIDB Bzimport 2026-08-27 08:42:37 UTC

A vulnerability was found in Undertow where the WebSocketContainer and its boot process do not allow setting the binaryBuffer and textBuffer sizes, along with session duration and async send timeout. These parameters default to infinite. This is a follow-up to CVE-2026-5680, as the initial fix allowed setting buffer sizes for certain types but left async send and session duration as infinite and inaccessible for configuration. An attacker could exploit these infinite defaults to cause resource exhaustion or an Out of Memory (OOME) condition on the server.