CVE-2026-106486: @backstage Plugin-Scaffolder-Backend-Module-Bitbucket-Cloud

High severity, CVSS 8.5. EPSS: 0.3% chance of exploitation in the next 30 days.

Backstage is an open framework for building developer portals. Prior to 0.3.10 in @backstage/plugin-scaffolder-backend-module-bitbucket-cloud and 0.2.25 in @backstage/plugin-scaffolder-backend-module-bitbucket-server, the Bitbucket pull-request Scaffolder actions did not sufficiently validate filesystem paths. An authenticated user who can execute an eligible template and influence an allowed Bitbucket repository could affect paths outside the expected working area, potentially compromising backend confidentiality, integrity, or availability. This issue is fixed in @backstage/plugin-scaffolder-backend-module-bitbucket-cloud 0.3.10 and @backstage/plugin-scaffolder-backend-module-bitbucket-server 0.2.25.

Affected products

• @backstage Plugin-Scaffolder-Backend-Module-Bitbucket-Cloud: before 0.3.10 (fixed in 0.3.10)
• @backstage Plugin-Scaffolder-Backend-Module-Bitbucket-Server: before 0.2.25 (fixed in 0.2.25)
• Backstage Backstage: before 1.54.6 (fixed in 1.54.6)

Published 2026-10-06. Last modified 2026-10-07.