Bug 2524775 (CVE-2026-47863)

Summary:	CVE-2026-47863 io.projectreactor/reactor-core: Reactor Core: Denial of Service in bufferTimeout operator
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	ant, avibelli, bgeorges, ccranfor, cescoffi, dandread, dkreling, fmongiar, gmalinko, gsmet, janstey, jmartisk, jnethert, jpechane, lthon, manderse, mosmerov, olubyans, pdelbell, pesilva, pgallagh, pjindal, probinso, rguimara, rruss, rstepani, rsvoboda, sbiarozk, tqvarnst
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in Reactor Core. Applications using the `Flux.bufferTimeout` operator with `fairBackpressure` enabled are vulnerable to a Denial of Service (DoS) condition. This occurs when upstream components deliver items during an active flush, causing the processing pipeline to permanently hang and making the application unresponsive.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-08-27 00:22:46 UTC

In Reactor Core, applications that use the Flux.bufferTimeout operator with fairBackpressure enabled are vulnerable to a Denial of Service (DoS) condition.
Reactor Core 3.8.0 - 3.8.6
Reactor Core 3.7.19 and earlier