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TI-2026-69170 Aliases CVE-2026-106563GHSA-r9ph-3637-55px

Improper entity validation exposes Kubernetes data in Backstage

Priority LOW 28CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · 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. Impact type from CWE-862.

Summary

Backstage before 1.54.1 and the @backstage/plugin-kubernetes-backend package before 0.21.8 are affected. Improper input validation (CWE-20) in a deprecated Kubernetes services endpoint lets an authenticated user with Kubernetes read permissions access workload data beyond their intended scope by supplying crafted entity data. The exposure is limited to read-only access to Kubernetes object metadata across configured clusters.

Written with Claude Haiku 5.5 from the sources below · 2026-11-03

Description from the CNA

Backstage is an open framework for building developer portals. Prior to 0.21.8, the @backstage/plugin-kubernetes-backend package is affected by improper entity validation in deprecated kubernetes services endpoint. An authenticated user with Kubernetes read permissions could access Kubernetes workload data beyond their intended scope by supplying crafted entity data to the deprecated services endpoint. The exposure is limited to read-only access to Kubernetes object metadata across configured clusters. This issue is fixed in version 0.21.8.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00225 13th percentileScored 2026-11-07
Fix Partial backstage (backstage): 1.54.1plugin-kubernetes-backend (@backstage): 0.21.8+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 1.54.11.54.1Patch availableCNA
backstageplugin-kubernetes-backendbefore 0.21.80.21.8Patch availableCNA
—@backstage/plugin-kubernetes-backend (npm)before 0.21.80.21.8Patch availableGHSA-r9ph-3637-55px
  • backstage Vendorbackstage Affected before 1.54.1 Fixed in 1.54.1 Patch available CNA
  • plugin-kubernetes-backend Vendorbackstage Affected before 0.21.8 Fixed in 0.21.8 Patch available CNA
  • @backstage/plugin-kubernetes-backend (npm) Vendor— Affected before 0.21.8 Fixed in 0.21.8 Patch available GHSA-r9ph-3637-55px

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:linuxfoundation:backstage\/plugin-kubernetes-backend:*:*:*:*:*:node.js:*:*before 0.21.8Vulnerablebackstage
cpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:*before 1.54.1Vulnerablebackstage
  • cpe:2.3:a:linuxfoundation:backstage\/plugin-kubernetes-backend:*:*:*:*:*:node.js:*:* Versions before 0.21.8 Vulnerable ·backstage
  • cpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:* Versions before 1.54.1 Vulnerable ·backstage

Remediation

Upgrade Backstage to 1.54.1 and @backstage/plugin-kubernetes-backend to 0.21.8. Red Hat Developer Hub 1 and Self-service automation portal 2 are affected, and Red Hat lists no available plan for them.

Written with Claude Haiku 5.5 from the sources below · 2026-11-03

  • Fix · CNA backstage (backstage) Fixed in 1.54.1
  • Fix · CNA plugin-kubernetes-backend (@backstage) Fixed in 0.21.8
  • Fix · GHSA-r9ph-3637-55px @backstage/plugin-kubernetes-backend (npm) Fixed in 0.21.8 Advisory →

Vendor assessments

Red Hat

Red Hat rating: Moderate. 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-2026-106563
  2. 2026-10-07 Alias added: GHSA-r9ph-3637-55px
  3. 2026-10-07 Fix available: npm/@backstage/[email protected] · GHSA-r9ph-3637-55px
  4. 2026-10-07 CVSS score added · GHSA-r9ph-3637-55px
  5. 2026-10-07 Weakness changed · GHSA-r9ph-3637-55px
  6. 2026-10-07 5 new references · GHSA-r9ph-3637-55px
  7. 2026-10-10 CISA SSVC decision points changed
  8. 2026-10-16 CVSS score added · NVD
  9. 2026-11-03 Affected versions changed · Red Hat
  10. 2026-11-03 CVSS score added · 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