Bug 2547199 (CVE-2026-106492)

Summary:	CVE-2026-106492 @backstage/backend-defaults: @backstage/backend-defaults: Access control bypass via improper service credential delegation
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	abarbaro, alizardo, dschmidt, ikhan, jchui, jhe, jlanda, kshier, ktsao, nboldt, oaljalju, psrna, rbobbitt, simaishi, stcannon, yguenane
Target Milestone:	---	Keywords:	Security
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Hardware:	All
OS:	Linux
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Doc Text:	A flaw was found in @backstage/backend-defaults. The package fails to properly preserve access restrictions during service credential delegation when requests are routed through plugin delegation paths. An authenticated service with limited privileges can exploit this issue to bypass access controls and perform unauthorized operations, such as modifying data on restricted plugins.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
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Description OSIDB Bzimport 2026-10-06 21:02:02 UTC

Backstage is an open framework for building developer portals. Prior to 0.16.1 and 0.17.8, the @backstage/backend-defaults package is affected by improper preservation of access restrictions during service credential delegation. An external service credential configured with access restrictions (e.g., read-only) could bypass those restrictions by routing requests through plugin delegation paths. This could allow a restricted service to perform operations beyond its intended scope, including write operations on plugins it was restricted to read-only access for. This issue is fixed in versions 0.16.1 and 0.17.8.