Vulnerability · Published Oct 6, 2026 · Assigned by GitHub_M
CVE-2026-106499Backstage: Secret-derived values may be exposed in scaffolder task logs
Medium 4.9
In plain English
A medium-severity sensitive data in logs in backstage from backstage. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend package could expose secret-derived values in Scaffolder task logs. Deployments that configure sensitive scaffolder.defaultEnvironment.secrets and allow an attacker to create or modify Scaffolder templates are affected. A template author could cause secret-derived values used during template iteration to be persisted and exposed to users who can access the resulting task logs. This issue is fixed in version 4.1.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @backstage/plugin-scaffolder-backend | 4.1.0 | GHSA-mfvq-x7vr-rgqg |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| backstage | backstage | < 1.54.6 |
| @backstage | plugin-scaffolder-backend | < 4.1.0 |
Weakness: CWE-532 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N