CVE-2026-106501

Backstage: Sensitive information exposure in Scaffolder

State: Published
Severity: 9.6 Critical
Published: Oct 6, 2026
Updated: Oct 7, 2026
Reserved: Oct 6, 2026

Description

Backstage is an open framework for building developer portals. Prior to 3.3.1, 3.4.1, 4.0.3 and 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by sensitive information exposure in scaffolder. An authenticated Backstage user who can read another user's Scaffolder task may receive internal execution data. In deployments where that data contains credentials for an external service, this may permit disclosure and unauthorized changes in that external service. This issue is fixed in versions 3.3.1, 3.4.1, 4.0.3 and 4.1.0.

Scores

CVSS	Score	Vector	Source
3.1	9.6 Critical	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N	GitHub_M

Weaknesses

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
CWE-201 Insertion of Sensitive Information Into Sent Data

Affected Products

Product	Versions
backstagebackstage	< 1.49.6Affected >= 1.50.0-next.0, < 1.50.5Affected >= 1.51.0-next.0, < 1.54.6Affected
plugin-scaffolder-backend@backstage	< 3.3.1Affected >= 3.4.0, < 3.4.1Affected >= 4.0.0, < 4.0.3Affected >= 4.0.4, < 4.1.0Affected

References

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