CVE-2026-106563

mediumpriority · track · 26OT risk · elevatedEPSS 0.002 · 13 %ileUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.22% (13th) EPSS

CVSS 6.5 · medium

Is it mine?

3 products

Check your exposure

Who says so?

2 sources

nvd · osv

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.15.3mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:Nsecondary · security-advisories@github.comexploitability 1.6 · impact 3.6

v3.15.3mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:Nsecondary · OSV

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USCWE-20USCWE-862USCWE-862US

affected products (3)

Products and version ranges known to be affected.

linuxfoundation backstage< 1.54.1nvdUScpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:*
linuxfoundation backstage/plugin-kubernetes-backend< 0.21.8nvdUScpe:2.3:a:linuxfoundation:backstage\/plugin-kubernetes-backend:*:*:*:*:*:*:*:*
npm @backstage/plugin-kubernetes-backend< 0.21.8osvUSpkg:npm/%40backstage/plugin-kubernetes-backend

advisories (1)

Vendor and ecosystem advisories describing this.

GHSA-r9ph-3637-55pxBackstage: Improper entity validation in deprecated Kubernetes services endpoint2026-10-07ghsa · osvUS
### 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/:serviceId` route by deploying a custom Kubernetes router that omits it. - Restrict access to the `kubernetes.resources.read` permission to limit the set of users who can reach the endpoint.

sources

Which sources assert this record, and when.

nvd osv NVD CVE.org MITRE

published 2026-10-07modified 2026-10-16

references (3) nvd

External citations — patches, advisories, analysis.

https://github.com/backstage/backstage/commit/2d5d3e77d630455d6d48cfa8f31fd3c126fd6f29Patch
https://github.com/backstage/backstage/releases/tag/v1.54.1PatchRelease Notes
https://github.com/backstage/backstage/security/advisories/GHSA-r9ph-3637-55pxMitigationVendor Advisory

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan