Summary
Backstage: Improper preservation of access restrictions during service credential delegation
Advisory details
Impact
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.
Patches
Patched in @backstage/backend-defaults version 0.17.8
Workarounds
If you're unable to upgrade immediately:
- If practical, replace restricted credentials with separate, purpose-specific unrestricted credentials scoped to trusted consumers.
- Restrict network-level access to Backstage backend API endpoints to trusted callers only.
References
- https://github.com/advisories/GHSA-cq7v-rfgc-5c7v
- https://github.com/backstage/backstage/security/advisories/GHSA-cq7v-rfgc-5c7v
- https://nvd.nist.gov/vuln/detail/CVE-2026-106492
- https://github.com/backstage/backstage/commit/40346245c53e1bf26dee56601e95c5c4ab9cc124
- https://github.com/backstage/backstage/commit/bc80ffdafbc92ff7b8c72347eace13cb8688fd33
- https://github.com/backstage/backstage/releases/tag/v1.49.6
- https://github.com/backstage/backstage/releases/tag/v1.54.6
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