CVE-2026-88064
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.
What this means for your business
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 8.8 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H- Weakness
- CWE-20
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-16
- Last modified
- 2026-09-16
- Sources
- NVD
References
- https://github.com/backstage/backstage/commit/017ace52d9b327ededc6704cf17799c875ae0f29
- https://github.com/backstage/backstage/commit/02cd7cdbb18b687446277b5602adaee7f1d53cbb
- https://github.com/backstage/backstage/commit/25125ee727a3de3418a8fa6a9e458cd5b73ecf26
- https://github.com/backstage/backstage/commit/a7d995f11a5d27f0efbdbe8bb6c21b06988c79c9
- https://github.com/backstage/backstage/commit/a900a9953c8f7ad3ba1906d1d257725a9996cc9d
- https://github.com/backstage/backstage/releases/tag/v1.50.5
- https://github.com/backstage/backstage/releases/tag/v1.54.6
- https://github.com/backstage/backstage/security/advisories/GHSA-292q-8mf5-h6g3