Description
Backstage is an open framework for building developer portals. Prior to 1.14.6 and from 1.15.0 until 1.15.4, the @backstage/plugin-techdocs-node package insufficiently validates mkdocs.yml supplied by an authenticated user who can register or modify a TechDocs source. Unsafe Python YAML tags, markdown_extensions names and configuration, theme options, and extra_templates values can reach the documentation generator and cause unintended code execution. The resulting impact is limited to the files, credentials, network access, and other resources available to the TechDocs backend or build container. This issue is fixed in versions 1.14.6 and 1.15.4.
Published: 2026-09-16
Score: 8.8 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

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Tracking

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History

Thu, 17 Sep 2026 06:30:00 +0000

Type Values Removed Values Added
First Time appeared Backstage
Backstage backstage
Vendors & Products Backstage
Backstage backstage

Wed, 16 Sep 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Wed, 16 Sep 2026 14:30:00 +0000

Type Values Removed Values Added
Description Backstage is an open framework for building developer portals. Prior to 1.14.6 and from 1.15.0 until 1.15.4, the @backstage/plugin-techdocs-node package insufficiently validates mkdocs.yml supplied by an authenticated user who can register or modify a TechDocs source. Unsafe Python YAML tags, markdown_extensions names and configuration, theme options, and extra_templates values can reach the documentation generator and cause unintended code execution. The resulting impact is limited to the files, credentials, network access, and other resources available to the TechDocs backend or build container. This issue is fixed in versions 1.14.6 and 1.15.4.
Title Backstage: Improper input validation in TechDocs MkDocs configuration
Weaknesses CWE-1336
CWE-20
References
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Subscriptions

Backstage Backstage
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-09-16T15:46:46.830Z

Reserved: 2026-09-09T21:22:45.434Z

Link: CVE-2026-88064

cve-icon Vulnrichment

Updated: 2026-09-16T15:46:36.744Z

cve-icon NVD

Status : Received

Published: 2026-09-16T15:18:04.297

Modified: 2026-09-16T16:17:19.897

Link: CVE-2026-88064

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-17T06:15:03Z

Weaknesses
  • CWE-1336

    Improper Neutralization of Special Elements Used in a Template Engine

  • CWE-20

    Improper Input Validation