Improper Handling of Case Sensitivity Affecting @backstage/plugin-scaffolder-backend package, versions <3.3.1>=3.4.0 <3.4.1>=4.0.0 <4.0.3>=4.0.4 <4.1.0
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-JS-BACKSTAGEPLUGINSCAFFOLDERBACKEND-20825392
- published11 Oct 2026
- disclosed7 Oct 2026
- creditUnknown
Introduced: 7 Oct 2026
NewCVE-2026-106503 (opens in a new tab)How to fix?
Upgrade @backstage/plugin-scaffolder-backend to version 3.3.1, 3.4.1, 4.0.3, 4.1.0 or higher.
Overview
@backstage/plugin-scaffolder-backend is a The Backstage backend plugin that helps you create new things
Affected versions of this package are vulnerable to Improper Handling of Case Sensitivity via isActionAuthorized in NunjucksWorkflowRunner.ts, where numeric or numeric-string values supplied as the path input to group-related scaffolder actions bypass permission condition checks. An authenticated attacker can pass a numeric path value to a group action, causing the authorization logic to skip evaluation of HAS_STRING_PROPERTY conditions and grant access that should be denied by the configured permission policy.