CVE-2026-106563

Backstage: Improper entity validation in deprecated Kubernetes services endpoint

Published Oct 7, 2026 CVSS 3.1 · 5.3 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Github GHSA Github GHSA GHSA-r9ph-3637-55px Backstage: Improper entity validation in deprecated Kubernetes services endpoint
History
Type Values Removed Values Added
First Time appeared Linuxfoundation
Linuxfoundation backstage
Linuxfoundation backstage\/plugin-kubernetes-backend
CPEs cpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:*
cpe:2.3:a:linuxfoundation:backstage\/plugin-kubernetes-backend:*:*:*:*:*:node.js:*:*
Vendors & Products Linuxfoundation
Linuxfoundation backstage
Linuxfoundation backstage\/plugin-kubernetes-backend
Type Values Removed Values Added
First Time appeared Backstage
Backstage backstage
Backstage plugin-kubernetes-backend
Vendors & Products Backstage
Backstage backstage
Backstage plugin-kubernetes-backend
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title Backstage: Improper entity validation in deprecated Kubernetes services endpoint
Weaknesses CWE-20
CWE-862
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 10, 2026, 2:28 AM
Reserved
Oct 6, 2026, 8:31 PM
Status
Analyzed
Published
Oct 7, 2026, 3:17 PM
Modified
Oct 16, 2026, 2:50 PM