Insertion of Sensitive Information into Log File Affecting @backstage/plugin-scaffolder-backend package, versions <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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- published11 Oct 2026
- disclosed7 Oct 2026
- creditUnknown
Introduced: 7 Oct 2026
NewCVE-2026-106504 (opens in a new tab)How to fix?
Upgrade @backstage/plugin-scaffolder-backend to version 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 Insertion of Sensitive Information into Log File via the NunjucksWorkflowRunner in plugins/scaffolder-backend/src/scaffolder/tasks/NunjucksWorkflowRunner.ts, where a denied scaffolder action causes the runner to throw a NotAllowedError that includes the full serialized action input in the error message. An authenticated attacker who triggers an unauthorized action can read the complete input object - which may contain secrets, tokens, or other sensitive configuration - from the resulting error response.