CVE-2026-106500

Backstage: Improper task state validation in Scaffolder backend

HIGH
8.5
CVSS Score
Published: October 6, 2026 at 09:29 PM UTC
Updated: October 13, 2026 at 02:38 PM UTC
4 products affected across 2 vendorsBackstageBackstage /plugin Scaffolder BackendBackstage

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Severity
HIGH8.5
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

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 improper task state validation in scaffolder backend. An authenticated user with permission to create and access Scaffolder tasks may, under specific timing and deployment conditions, affect files accessible to the Backstage backend. If backend application files are writable, the confidentiality, integrity, and availability of the backend may be compromised. This issue is fixed in versions 3.3.1, 3.4.1, 4.0.3 and 4.1.0.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

References (7)

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.5HIGHGitHub_M
Attack Vector
NETWORK
Complexity
HIGH
Privileges
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-59CWE-362

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