CVE-2026-88064highCWE-1336CWE-20

CVE-2026-88064: high-severity vulnerability in backstage

Backstage: Improper input validation in TechDocs MkDocs configuration

Published

Follow this CVE+ Monitor backstage

E-mail alert when it lands in KEV, gets a public PoC or its score goes up.

21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.8epss 1.2%
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected products
backstage · backstage
Related CVEs — backstage

In the same product, most dangerous first.

CVE-2023-35926HIGHInsecure sandbox in Backstage Scaffolder pluginEPSS 1.9%CVE-2021-41151MEDIUMPath Traversal in @backstage/plugin-scaffolder-backendEPSS 1.3%CVE-2021-32662MEDIUMTechDocs mkdocs.yml path traversalEPSS 1.3%CVE-2021-32660MEDIUMTechDocs content sanitization bypassEPSS 1.3%CVE-2021-43783HIGHPath Traversal in @backstage/plugin-scaffolder-backendEPSS 1.2%CVE-2021-32661MEDIUMTechDocs object element script injectionEPSS 1.2%