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TI-2026-69074 Aliases CVE-2026-106500GHSA-xvgh-hmx8-9xxf

Race condition in Backstage scaffolder backend task handling

Priority LOW 39CWE-362Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 2 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat.

Summary

Backstage's @backstage/plugin-scaffolder-backend package is affected before 3.3.1, from 3.4.0 before 3.4.1, from 4.0.0 before 4.0.3 and from 4.0.4 before 4.1.0. A race condition (CWE-362) in task state validation lets an authenticated user who can create and access Scaffolder tasks affect files the backend can access. If backend application files are writable, the backend's confidentiality, integrity and availability may be compromised.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00336 27th percentileScored 2026-11-07
Fix Partial backstage (backstage): 1.49.6, 1.50.5, 1.54.6plugin-scaffolder-backend (@backstage): 3.3.1, 3.4.1, 4.0.3 +1+1 more productRed Hat: 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
backstagebackstagebefore 1.49.6; 1.50.0-next.0 to before 1.50.5; 1.51.0-next.0 to before 1.54.61.49.6, 1.50.5, 1.54.6Patch availableCNA
backstageplugin-scaffolder-backendbefore 3.3.1; 3.4.0 to before 3.4.1; 4.0.0 to before 4.0.3; 4.0.4 to before 4.1.03.3.1, 3.4.1, 4.0.3, 4.1.0Patch availableCNA
—@backstage/plugin-scaffolder-backend (npm)before 4.1.04.1.0Patch availableGHSA-xvgh-hmx8-9xxf
  • backstage Vendorbackstage Affected before 1.49.6; 1.50.0-next.0 to before 1.50.5; 1.51.0-next.0 to before 1.54.6 Fixed in 1.49.6, 1.50.5, 1.54.6 Patch available CNA
  • plugin-scaffolder-backend Vendorbackstage Affected before 3.3.1; 3.4.0 to before 3.4.1; 4.0.0 to before 4.0.3; 4.0.4 to before 4.1.0 Fixed in 3.3.1, 3.4.1, 4.0.3, 4.1.0 Patch available CNA
  • @backstage/plugin-scaffolder-backend (npm) Vendor— Affected before 4.1.0 Fixed in 4.1.0 Patch available GHSA-xvgh-hmx8-9xxf

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:linuxfoundation:backstage\/plugin-scaffolder-backend:*:*:*:*:*:*:*:*before 3.3.1; 3.4.0 to before 3.4.1; 4.0.0 to before 4.0.3; 4.0.4 to before 4.1.0Vulnerablebackstage
cpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:*before 1.49.6; 1.50.0 to before 1.50.5; 1.51.0 to before 1.54.6Vulnerablebackstage
  • cpe:2.3:a:linuxfoundation:backstage\/plugin-scaffolder-backend:*:*:*:*:*:*:*:* Versions before 3.3.1; 3.4.0 to before 3.4.1; 4.0.0 to before 4.0.3; 4.0.4 to before 4.1.0 Vulnerable ·backstage
  • cpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:* Versions before 1.49.6; 1.50.0 to before 1.50.5; 1.51.0 to before 1.54.6 Vulnerable ·backstage

Remediation

Fixed versions of @backstage/plugin-scaffolder-backend are 3.3.1, 3.4.1, 4.0.3 and 4.1.0. The sources list no fixed version for backstage. Red Hat reports no fix plan available for Red Hat Developer Hub 1 and Self-service automation portal 2.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA backstage (backstage) Fixed in 1.49.6, 1.50.5, 1.54.6
  • Fix · CNA plugin-scaffolder-backend (@backstage) Fixed in 3.3.1, 3.4.1, 4.0.3, 4.1.0
  • Fix · GHSA-xvgh-hmx8-9xxf @backstage/plugin-scaffolder-backend (npm) Fixed in 4.1.0 Advisory →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Developer Hub 1AffectedNo fix yet
Self-service automation portal 2AffectedNo fix yet

Timeline

  1. 2026-10-07 Threatist record created from CVE-2026-106500
  2. 2026-10-07 Affected versions changed · Red Hat
  3. 2026-10-07 CVSS score added · Red Hat
  4. 2026-10-07 CISA SSVC decision points changed
  5. 2026-10-07 Priority changed: MEDIUM → LOW
  6. 2026-10-07 Alias added: GHSA-xvgh-hmx8-9xxf
  7. 2026-10-07 Fix available: npm/@backstage/[email protected] · GHSA-xvgh-hmx8-9xxf
  8. 2026-10-07 CVSS score added · GHSA-xvgh-hmx8-9xxf
  9. 2026-10-07 Weakness changed · GHSA-xvgh-hmx8-9xxf
  10. 2026-10-07 9 new references · GHSA-xvgh-hmx8-9xxf
  11. 2026-10-27 Affected versions changed · Red Hat

References

Patch 6

Advisory 2

Other 1

  • TI-2023-17988 Insecure sandbox in Backstage Scaffolder plugin CVSS 3.1CRITICAL 9.9
  • TI-2026-69075 Sensitive information exposure in Backstage Scaffolder CVSS 3.1CRITICAL 9.6
  • TI-2026-69061 Path traversal in Backstage Bitbucket pull-request scaffolder actions CVSS 3.1CRITICAL 9.9
  • TI-2026-60083 Backstage: Improper input validation in TechDocs MkDocs configuration CVSS 3.1HIGH 8.8
  • TI-2026-69165 Backstage TechDocs config flaw allows code execution CVSS 3.1HIGH 8.8
  • TI-2026-69083 Code injection via MkDocs theme configuration in Backstage TechDocs CVSS 3.1HIGH 8.8
See all 52 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences