Improper Authorization Affecting @backstage/backend-defaults package, versions <0.17.8
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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- published18 Oct 2026
- disclosed15 Oct 2026
- creditUnknown
Introduced: 15 Oct 2026
NewCVE-2026-106495 (opens in a new tab)How to fix?
Upgrade @backstage/backend-defaults to version 0.17.8 or higher.
Overview
@backstage/backend-defaults is a Backend defaults used by Backstage backend apps
Affected versions of this package are vulnerable to Improper Authorization via the actions registry endpoint /.backstage/actions/v1/actions in DefaultActionsRegistryService, where the isActionAllowed filter was not applied before passing action entries to the permissions check. An authenticated attacker can observe actions that should be restricted, resulting in unauthorized disclosure of available action metadata and the ability to invoke actions that should not be accessible to them.