CVE-2026-106503

Backstage: Scaffolder action input authorization bypass

State
Published
Severity
8.1 High
Published
Oct 6, 2026
Updated
Oct 9, 2026
Reserved
Oct 6, 2026

Read the record on cve.org

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.

Scores

CVSSScoreVectorSource
3.18.1 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:NGitHub_M

Weaknesses

  • CWE-178 Improper Handling of Case Sensitivity
  • CWE-284 Improper Access Control

Affected Products

ProductVersions
backstagebackstage
  • < 1.49.6Affected
  • >= 1.50.0-next.0, < 1.50.5Affected
  • >= 1.51.0-next.0, < 1.54.6Affected
plugin-scaffolder-backend@backstage
  • < 3.3.1Affected
  • >= 3.4.0, < 3.4.1Affected
  • >= 4.0.0, < 4.0.3Affected
  • >= 4.0.4, < 4.1.0Affected

References

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