Backstage: Improper entity validation in deprecated Kubernetes services endpoint
Impact
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.
Patches
Patched in @backstage/plugin-kubernetes-backend version 0.21.8.
Workarounds
- Disable the deprecated
/services/:serviceIdroute by deploying a custom Kubernetes router that omits it. - Restrict access to the
kubernetes.resources.readpermission to limit the set of users who can reach the endpoint.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| npm package | @backstage/plugin-kubernetes-backend | < 0.21.8 | 0.21.8 |
References
- https://github.com/backstage/backstage/security/advisories/GHSA-r9ph-3637-55px
- https://nvd.nist.gov/vuln/detail/CVE-2026-106563
- https://github.com/backstage/backstage/commit/2d5d3e77d630455d6d48cfa8f31fd3c126fd6f29
- https://github.com/backstage/backstage
- https://github.com/backstage/backstage/releases/tag/v1.54.1
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N- Weakness (CWE)
CWE-20, CWE-862- Platform
- npm
- Package
@backstage/plugin-kubernetes-backend- Disclosed
- 07.10.2026
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-r9ph-3637-55px - CC BY 4.0
Vulnerability history: @backstage/plugin-kubernetes-backend
All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 3
- First → latest
- 10.2026 10.2026
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Medium 2
- Low 1
Disclosures per year
- 2026: 3
-
Backstage: Improper entity validation in deprecated Kubernetes services endpoint this entry
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