# CVE-2026-106507: Backstage: TechDocs arbitrary file read via mkdocs snippets

> An authenticated user can read arbitrary files outside the documentation boundary via unsafe path resolution in TechDocs.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 6 Oct 2026
- **Updated:** 7 Oct 2026
- **Also known as:** GHSA-vmqh-7cj9-mvcj

## What is CVE-2026-106507?

CVE-2026-106507 is a medium-severity path traversal vulnerability in Linuxfoundation Backstage, published on 6 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Backstage is an open framework for building developer portals. Prior to 1.15.4, the @backstage/plugin-techdocs-node package is affected by techdocs arbitrary file read via mkdocs snippets. Unsafe path resolution in TechDocs source tree handling allows an authenticated user who can register documentation sources to include content from outside the intended documentation boundary. Depending on deployment, this may expose files readable by the build process. This issue is fixed in version 1.15.4.

Weakness: CWE-61 (UNIX Symbolic Link (Symlink) Following), CWE-59 (Improper Link Resolution Before File Access)

## Which versions are affected by CVE-2026-106507?

It affects 2 products.


Products: Linuxfoundation Backstage, Linuxfoundation Backstage Plugin-Techdocs-Node.

## How do I fix CVE-2026-106507?

No fix has been published for CVE-2026-106507 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-106507 being exploited?

There is no known exploitation of CVE-2026-106507 in the wild and no public exploit code.

## Other vulnerabilities in Linuxfoundation Backstage

- [CVE-2026-106501](https://insights.sbomify.com/CVE-2026-106501/): Backstage: Sensitive information exposure in Scaffolder (critical 9.6)
- [CVE-2026-106558](https://insights.sbomify.com/CVE-2026-106558/): Backstage: Improper validation of TechDocs MkDocs configuration (high 8.8)
- [CVE-2026-88064](https://insights.sbomify.com/CVE-2026-88064/): Backstage: Improper input validation in TechDocs MkDocs configuration (high 8.8)
- [CVE-2026-106459](https://insights.sbomify.com/CVE-2026-106459/): Backstage: Improper input validation in Sentry scaffolder actions (high 8.5)
- [CVE-2026-106486](https://insights.sbomify.com/CVE-2026-106486/): Backstage: Improper filesystem validation in Bitbucket pull-request scaffolder actions (high 8.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-106507 and fix it if it is affected.

What it is: CVE-2026-106507 is a medium-severity path traversal vulnerability in Linuxfoundation Backstage, published on 6 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-106507 in the wild and no public exploit code.

Affected product: Linuxfoundation Backstage. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-106507/ (Markdown: https://insights.sbomify.com/CVE-2026-106507/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-106507
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-106507
- OSV: https://osv.dev/vulnerability/CVE-2026-106507

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-106507/
Summaries are generated and may contain mistakes; the official description above is the record.