Backstage: Scaffolder action input authorization bypass
Summary
| CVE | CVE-2026-106503 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-06 22:17:05 UTC |
| Updated | 2026-10-06 22:17:05 UTC |
| Description | Backstage is an open framework for building developer portals. Prior to 3.3.1, 3.4.1, 4.0.3 and 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by scaffolder action input authorization bypass. An authenticated user with access to affected Scaffolder templates could bypass configured action restrictions. Depending on integration credentials, this could grant unauthorized access to repositories and related source-control resources. This issue is fixed in versions 3.3.1, 3.4.1, 4.0.3 and 4.1.0. |
Risk And Classification
Primary CVSS: v3.1 8.1 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Problem Types: CWE-178 | CWE-284 | CWE-178 CWE-178: Improper Handling of Case Sensitivity | CWE-284 CWE-284: Improper Access Control
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 8.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |
| 3.1 | CNA | DECLARED | 8.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Backstage | Backstage | affected < 1.49.6 | Not specified |
| CNA | Backstage | Backstage | affected >= 1.50.0-next.0, < 1.50.5 | Not specified |
| CNA | Backstage | Backstage | affected >= 1.51.0-next.0, < 1.54.6 | Not specified |
| CNA | @backstage | Plugin-scaffolder-backend | affected < 3.3.1 | Not specified |
| CNA | @backstage | Plugin-scaffolder-backend | affected >= 3.4.0, < 3.4.1 | Not specified |
| CNA | @backstage | Plugin-scaffolder-backend | affected >= 4.0.0, < 4.0.3 | Not specified |
| CNA | @backstage | Plugin-scaffolder-backend | affected >= 4.0.4, < 4.1.0 | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/backstage/backstage/commit/e307e4f487103d815e484291b3fda778ab... | [email protected] | github.com | |
| github.com/backstage/backstage/releases/tag/v1.50.5 | [email protected] | github.com | |
| github.com/backstage/backstage/releases/tag/v1.49.6 | [email protected] | github.com | |
| github.com/backstage/backstage/security/advisories/GHSA-hmp2-4m7g-22cv | [email protected] | github.com | |
| github.com/backstage/backstage/commit/11c1384c0649b8ab26391c6a4e4f34b80a... | [email protected] | github.com | |
| github.com/backstage/backstage/releases/tag/v1.54.6 | [email protected] | github.com | |
| github.com/backstage/backstage/commit/a91ed72d540e80b62a73b39bb1563ff501... | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.