CVE-2026-106508: Linuxfoundation Backstage

Medium severity, CVSS 6.5. EPSS: 0.3% chance of exploitation in the next 30 days.

Backstage is an open framework for building developer portals. Prior to 1.15.4, the @backstage/plugin-techdocs-node package is affected by potential file exposure through local techdocs publisher. When using the local TechDocs publisher (techdocs.publisher.type: 'local'), it was possible for the documentation serving endpoint to follow filesystem references outside the intended documentation tree, potentially exposing host files to authenticated users. This is mitigated by the fact that exploration requires preconditions that do not arise through normal MkDocs operation. Cloud-based publishers (S3, GCS, Azure Blob Storage) are not affected. This issue is fixed in version 1.15.4.

Affected products

• Linuxfoundation Backstage: before 1.54.6 (fixed in 1.54.6)
• Linuxfoundation Backstage Plugin-Techdocs-Node: before 1.15.4 (fixed in 1.15.4)

Published 2026-10-06. Last modified 2026-10-09.