CVE-2026-106557
Backstage: Improper input validation in TechDocs Markdown extension configuration
CVSS Score
7.7
EPSS Score
0.0%
EPSS Percentile
0th
Backstage is an open framework for building developer portals. Prior to 1.14.6 and 1.15.4, the @backstage/plugin-techdocs-node package did not sufficiently validate TechDocs Markdown extension configuration. An authenticated user who can register or modify documentation sources may cause a TechDocs build to access resources outside the intended documentation boundary, potentially exposing backend-host data or internal network resources. This issue is fixed in versions 1.14.6 and 1.15.4 when pymdown-extensions 10.21.3 or later is also used, normally through mkdocs-techdocs-core 1.7.0 or later.
| CWE | CWE-22 CWE-918 |
| Vendor | backstage |
| Product | backstage |
| Published | Oct 7, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
backstage / backstage
< 1.50.5 >= 1.51.0-next.0, < 1.54.6
@backstage / plugin-techdocs-node
< 1.14.6 >= 1.15.0, < 1.15.4
References
github.com: https://github.com/backstage/backstage/security/advisories/GHSA-f7v3-xhm6-w245 github.com: https://github.com/backstage/backstage/commit/017ace52d9b327ededc6704cf17799c875ae0f29 github.com: https://github.com/backstage/backstage/commit/2d9de4ca117a529de4b6ed7dfb7aa507ca7b3f91 github.com: https://github.com/backstage/backstage/releases/tag/v1.50.5 github.com: https://github.com/backstage/backstage/releases/tag/v1.54.6