CVE-2026-106492
Backstage: Improper preservation of access restrictions during service credential delegation
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- High
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
Backstage: Improper preservation of access restrictions during service credential delegation
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.
- Record
CVE-2026-106492- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L - Weakness
- CWE-269, CWE-863
- Updated
- 2026-11-02
EUVDEUVD-2026-94012
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.
- Record
EUVD-2026-94012- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-cq7v-rfgc-5c7v
Backstage: Improper preservation of access restrictions during service credential delegation
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.
- Record
GHSA-cq7v-rfgc-5c7v- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L - Weakness
- CWE-269, CWE-863
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-106492- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-269, CWE-863
- Updated
- 2026-11-02
OSV
Backstage: Improper preservation of access restrictions during service credential delegation
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.
- Record
CVE-2026-106492- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L - Weakness
- CWE-269, CWE-863
- Updated
- 2026-11-02
OSVGHSA-cq7v-rfgc-5c7v
Backstage: Improper preservation of access restrictions during service credential delegation
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.
- Record
GHSA-cq7v-rfgc-5c7v- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L - Weakness
- CWE-269, CWE-863
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
@backstage/backend-defaultsnpm |
before 0.17.8 | 0.17.8 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-106492 is a high vulnerability (CVSS 7.6) in @backstage Backend-defaults, published October 6, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.21%, the 10th percentile. Fixed in @backstage/backend-defaults 0.17.8.
References
github.com/backstage/backstage/security/advisories/GHSA-cq7v-rfgc-5c7v
nvd.nist.gov/vuln/detail/CVE-2026-106492