CVE-2026-106492

mediumpriority · track · 26OT risk · elevatedEPSS 0.002 · 11 %ileUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.21% (11th) EPSS

CVSS 6.5 · medium

Is it mine?

5 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 0.16.1 and 0.17.8, the @backstage/backend-defaults package is affected by improper preservation of access restrictions during service credential delegation. An external service credential configured with access restrictions (e.g., read-only) could bypass those restrictions by routing requests through plugin delegation paths. This could allow a restricted service to perform operations beyond its intended scope, including write operations on plugins it was restricted to read-only access for. This issue is fixed in versions 0.16.1 and 0.17.8.

cvss

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

7.6

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6–7.6

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

v3.17.6highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:Lsecondary · security-advisories@github.comexploitability 2.8 · impact 4.7

v3.17.6highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:Lsecondary · OSV

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/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-269USCWE-269USCWE-863USCWE-863US

affected products (5)

Products and version ranges known to be affected.

linuxfoundation backstage< 1.49.6nvdUScpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:*
linuxfoundation backstage1.50.0 → 1.54.6nvdUScpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:*
linuxfoundation backstage/backend-defaults< 0.16.1nvdUScpe:2.3:a:linuxfoundation:backstage\/backend-defaults:*:*:*:*:*:*:*:*
linuxfoundation backstage/backend-defaults0.17.0 → 0.17.8nvdUScpe:2.3:a:linuxfoundation:backstage\/backend-defaults:*:*:*:*:*:*:*:*
npm @backstage/backend-defaults< 0.17.8osvUSpkg:npm/%40backstage/backend-defaults

advisories (1)

Vendor and ecosystem advisories describing this.

GHSA-cq7v-rfgc-5c7vBackstage: Improper preservation of access restrictions during service credential delegation2026-10-07ghsa · osvUS
### Impact An external service credential configured with access restrictions (e.g., read-only) could bypass those restrictions by routing requests through plugin delegation paths. This could allow a restricted service to perform operations beyond its intended scope, including write operations on plugins it was restricted to read-only access for. ### Patches Patched in `@backstage/backend-defaults` version `0.17.8` ### Workarounds If you're unable to upgrade immediately: - If practical, replace restricted credentials with separate, purpose-specific unrestricted credentials scoped to trusted consumers. - Restrict network-level access to Backstage backend API endpoints to trusted callers only.

sources

Which sources assert this record, and when.

nvd osv NVD CVE.org MITRE

published 2026-10-06modified 2026-10-22

references (5) nvd

External citations — patches, advisories, analysis.

https://github.com/backstage/backstage/commit/40346245c53e1bf26dee56601e95c5c4ab9cc124Patch
https://github.com/backstage/backstage/commit/bc80ffdafbc92ff7b8c72347eace13cb8688fd33Patch
https://github.com/backstage/backstage/releases/tag/v1.49.6PatchRelease Notes
https://github.com/backstage/backstage/releases/tag/v1.54.6PatchRelease Notes
https://github.com/backstage/backstage/security/advisories/GHSA-cq7v-rfgc-5c7vMitigationVendor 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