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TI-2026-69062 Aliases CVE-2026-106487GHSA-h53x-hjx6-25gr

Unsupported catalog cluster auth mode in Backstage Kubernetes backend

Priority LOW 22CWE-441Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · None · None
Fix status
Partial Red Hat: 2 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat.

Summary

The @backstage/plugin-kubernetes-backend package before 0.21.10 in Backstage has an unsupported catalog cluster authentication mode. The backend uses its own in-cluster identity for catalog cluster discovery, and that credential is not sent to the catalog-supplied endpoint, a confused deputy flaw (CWE-441). A user who can create or modify kubernetes-cluster Resource entities, with the required endpoint permissions and pod RBAC, could expose Kubernetes resources readable by that identity.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

Backstage is an open framework for building developer portals. Prior to 0.21.10, the @backstage/plugin-kubernetes-backend package is affected by unsupported catalog cluster authentication mode in kubernetes backend. Deployments using catalog cluster discovery may be affected when catalog contributors can create or modify kubernetes-cluster Resource entities. With the required endpoint permissions and pod RBAC, the backend can use its local in-cluster identity, potentially exposing Kubernetes resources readable by that identity. The credential is used only with the local in-cluster API endpoint and is not sent to the catalog-supplied endpoint. This issue is fixed in version 0.21.10.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00263 18th percentileScored 2026-11-07
Fix Partial backstage (backstage): 1.54.6plugin-kubernetes-backend (@backstage): 0.21.10+1 more productRed Hat: 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
backstagebackstagebefore 1.54.61.54.6Patch availableCNA
backstageplugin-kubernetes-backendbefore 0.21.100.21.10Patch availableCNA
—@backstage/plugin-kubernetes-backend (npm)before 0.21.100.21.10Patch availableGHSA-h53x-hjx6-25gr
  • backstage Vendorbackstage Affected before 1.54.6 Fixed in 1.54.6 Patch available CNA
  • plugin-kubernetes-backend Vendorbackstage Affected before 0.21.10 Fixed in 0.21.10 Patch available CNA
  • @backstage/plugin-kubernetes-backend (npm) Vendor— Affected before 0.21.10 Fixed in 0.21.10 Patch available GHSA-h53x-hjx6-25gr

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:linuxfoundation:backstage\/plugin-kubernetes-backend:*:*:*:*:*:node.js:*:*before 0.21.10Vulnerablebackstage
cpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:*before 1.54.6Vulnerablebackstage
  • cpe:2.3:a:linuxfoundation:backstage\/plugin-kubernetes-backend:*:*:*:*:*:node.js:*:* Versions before 0.21.10 Vulnerable ·backstage
  • cpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:* Versions before 1.54.6 Vulnerable ·backstage

Remediation

Upgrade @backstage/plugin-kubernetes-backend to version 0.21.10, which fixes it. The sources list no fixed version for backstage. Red Hat has no plan available for Red Hat Developer Hub 1 or Self-service automation portal 2.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA backstage (backstage) Fixed in 1.54.6
  • Fix · CNA plugin-kubernetes-backend (@backstage) Fixed in 0.21.10
  • Fix · GHSA-h53x-hjx6-25gr @backstage/plugin-kubernetes-backend (npm) Fixed in 0.21.10 Advisory →

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Developer Hub 1AffectedNo fix yet: Fix deferred
Self-service automation portal 2AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-07 Threatist record created from CVE-2026-106487
  2. 2026-10-07 Alias added: GHSA-h53x-hjx6-25gr
  3. 2026-10-07 Fix available: npm/@backstage/[email protected] · GHSA-h53x-hjx6-25gr
  4. 2026-10-07 CVSS score added · GHSA-h53x-hjx6-25gr
  5. 2026-10-07 Weakness changed · GHSA-h53x-hjx6-25gr
  6. 2026-10-07 5 new references · GHSA-h53x-hjx6-25gr
  7. 2026-10-08 Affected versions changed · Red Hat
  8. 2026-10-08 CVSS score added · Red Hat
  9. 2026-10-09 CISA SSVC decision points changed
  10. 2026-10-23 CVSS score added · NVD
  11. 2026-10-27 Affected versions changed · Red Hat

References

Patch 2

Advisory 2

Other 1

  • TI-2023-17988 Insecure sandbox in Backstage Scaffolder plugin CVSS 3.1CRITICAL 9.9
  • TI-2026-69075 Sensitive information exposure in Backstage Scaffolder CVSS 3.1CRITICAL 9.6
  • TI-2026-69061 Path traversal in Backstage Bitbucket pull-request scaffolder actions CVSS 3.1CRITICAL 9.9
  • TI-2026-60083 Backstage: Improper input validation in TechDocs MkDocs configuration CVSS 3.1HIGH 8.8
  • TI-2026-69165 Backstage TechDocs config flaw allows code execution CVSS 3.1HIGH 8.8
  • TI-2026-69083 Code injection via MkDocs theme configuration in Backstage TechDocs CVSS 3.1HIGH 8.8
See all 52 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences