CVE-2023-35926
Backstage Scaffolder plugin has insecure sandbox
Impact
The Backstage scaffolder-backend plugin uses a templating library that requires a sandbox, as it by design allows for code injection. The library used for this sandbox so far has been `vm2`, but in light of several past vulnerabilities and existing vulnerabilities that may not have a fix, the plugin has switched to using a different sandbox library. ### Impact A malicious actor with write access to a registered scaffolder template could manipulate the template in a way that allows for remote code execution on the scaffolder-backend instance. This was only exploitable in the template YAML definition itself and not by user input data. ### Patches This is vulnerability is fixed in version 1.15.0 of `@backstage/plugin-scaffolder-backend`. ### Workarounds Note that the [Backstage Threat Model](https://backstage.io/docs/overview/threat-model) states that scaffolder templates are considered to be a sensitive area that with the recommendation that you control access and perform manual reviews of changes to the scaffolder templates. The exploit is of a nature where it is easily discoverable in manual review.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| npm | @backstage/plugin-scaffolder-backend | < 1.15.0 | 1.15.0 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Linuxfoundation | Backstage | before 1.15.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/backstage/backstage/commit/fb7375507d56faedcb7bb3665480070593c8949a
- https://github.com/backstage/backstage/releases/tag/v1.15.0
- https://github.com/backstage/backstage/security/advisories/GHSA-wg6p-jmpc-xjmr
- https://github.com/advisories/GHSA-wg6p-jmpc-xjmr
- https://nvd.nist.gov/vuln/detail/CVE-2023-35926