Summary
Backstage: Improper access control in backend action invocation
Advisory details
Impact
An authenticated user could invoke actions that an operator had excluded through action configuration. Existing action permissions and downstream authorization remain enforced.
Patches
Patched in @backstage/backend-defaults version 0.17.8
Workarounds
Limit access to action invocation endpoints to trusted service callers until upgrading.
References
- https://github.com/advisories/GHSA-3xr5-8w6c-p5gw
- https://github.com/backstage/backstage/security/advisories/GHSA-3xr5-8w6c-p5gw
- https://nvd.nist.gov/vuln/detail/CVE-2026-106495
- https://github.com/backstage/backstage/commit/a8fb34a990a69bcb745e85a3213cf9e5ba2d31a3
- https://github.com/backstage/backstage/releases/tag/v1.54.6
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