CVE-2026-106556 (GCVE-0-2026-106556)

Vulnerability from cvelistv5 – Published: 2026-10-07 14:39 – Updated: 2026-10-07 16:16
VLAI
Title
Backstage: Configuration bypass in TechDocs mkdocs.yml sanitization
Summary
Backstage is an open framework for building developer portals. Prior to 1.14.6, the @backstage/plugin-techdocs-node package is affected by configuration bypass in techdocs mkdocs.yml sanitization. Insufficient validation of MkDocs configuration during TechDocs generation could allow an authenticated user who can register or modify documentation sources to execute arbitrary commands in the build environment. Impact is limited to resources accessible to the TechDocs backend or build container. This issue is fixed in versions 1.14.6 and 1.15.4.
Severity
7.7 (High)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-07 16:15 UTC
CWE
  • CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
  • CWE-184 - Incomplete List of Disallowed Inputs
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7580 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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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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