CVE-2026-106503: high-severity vulnerability in backstage
Backstage: Scaffolder action input authorization bypass
Published
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.1epss 0.4%
exploitation probability
0.4%top 73% of all CVEs
observed exploitation
nono source reports it
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 scaffolder action input authorization bypass. An authenticated user with access to affected Scaffolder templates could bypass configured action restrictions. Depending on integration credentials, this could grant unauthorized access to repositories and related source-control resources. This issue is fixed in versions 3.3.1, 3.4.1, 4.0.3 and 4.1.0.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Related CVEs — backstage
In the same product, most dangerous first.
CVE-2023-35926HIGHInsecure sandbox in Backstage Scaffolder pluginEPSS 1.9%CVE-2021-41151MEDIUMPath Traversal in @backstage/plugin-scaffolder-backendEPSS 1.3%CVE-2021-32662MEDIUMTechDocs mkdocs.yml path traversalEPSS 1.3%CVE-2021-32660MEDIUMTechDocs content sanitization bypassEPSS 1.3%CVE-2021-43783HIGHPath Traversal in @backstage/plugin-scaffolder-backendEPSS 1.2%CVE-2021-32661MEDIUMTechDocs object element script injectionEPSS 1.2%
References
https://github.com/backstage/backstage/commit/11c1384c0649b8ab26391c6a4e4f34b80ab0d188https://github.com/backstage/backstage/commit/a91ed72d540e80b62a73b39bb1563ff5018d52d1https://github.com/backstage/backstage/commit/e307e4f487103d815e484291b3fda778ab9983bfhttps://github.com/backstage/backstage/releases/tag/v1.49.6https://github.com/backstage/backstage/releases/tag/v1.50.5https://github.com/backstage/backstage/releases/tag/v1.54.6https://github.com/backstage/backstage/security/advisories/GHSA-hmp2-4m7g-22cv