CVE-2026-106557 (GCVE-0-2026-106557)

Vulnerability from cvelistv5 – Published: 2026-10-07 16:22 – Updated: 2026-10-07 17:47
VLAI
Title
Backstage: Improper input validation in TechDocs Markdown extension configuration
Summary
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.
Severity
7.7 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-07 17:47 UTC
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
  • CWE-918 - Server-Side Request Forgery (SSRF)
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7639 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
backstage backstage Affected: < 1.50.5
Affected: >= 1.51.0-next.0, < 1.54.6
guessed Create a notification for this product.
@backstage plugin-techdocs-node Affected: < 1.14.6
Affected: >= 1.15.0, < 1.15.4
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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