CVE-2026-29186 (GCVE-0-2026-29186)
Vulnerability from cvelistv5
Published
2026-03-07 15:03
Modified
2026-03-09 20:24
CWE
  • CWE-434 - Unrestricted Upload of File with Dangerous Type
  • CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
Summary
Backstage is an open framework for building developer portals. Prior to version 1.14.3, this is a configuration bypass vulnerability that enables arbitrary code execution. The @backstage/plugin-techdocs-node package uses an allowlist to filter dangerous MkDocs configuration keys during the documentation build process. A gap in this allowlist allows attackers to craft an mkdocs.yml that causes arbitrary Python code execution, completely bypassing TechDocs' security controls. This issue has been patched in version 1.14.3.
Impacted products
Vendor Product Version
backstage backstage Version: < 1.14.3
Create a notification for this product.
Show details on NVD website


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