CVE-2023-35926 json
Insecure sandbox in Backstage Scaffolder plugin
published 2023-06-21 3 y ago modified 2026-09-10 1 mo ago also GHSA-wg6p-jmpc-xjmr , EUVD-2023-1899
- cvss
- 8.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.9%
- EPSS 1.9% chance of exploitation in 30 days, percentile 79%
- public exploits
- 0
- none known
Summary
Backstage is an open platform for building developer portals. The Backstage scaffolder-backend plugin uses a templating library that requires 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. 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. This is vulnerability is fixed in version 1.15.0 of `@backstage/plugin-scaffolder-backend`.
Patch / fix
- npm @backstage/plugin-scaffolder-backend 1.15.0
- linuxfoundation backstage 1.15.0
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 23 mo ago
Exploit prediction
1.89% chance of exploitation in the next 30 days, higher than 79% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H |
| NVD | 3.1 | 9.9 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| GitHub | 3.1 | 8.0 | CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | @backstage/plugin-scaffolder-backend | <1.15.0 |
1.15.0 |
Affected products
- backstage backstage
Classification
- Weakness
-
- CWE-94 Improper Control of Generation of Code
References
-
github.com
/backstage/backstage/commit/fb7375507d56faedcb7bb3665480070593c8949a
web, patch
-
github.com
/backstage/backstage/security/advisories/GHSA-wg6p-jmpc-xjmr
web, vendor-advisory
-
github.com
/backstage/backstage/releases/tag/v1.15.0
web, release-notes
-
nvd.nist.gov
/vuln/detail/CVE-2023-35926
advisory
-
github.com
/backstage/backstage
package
Sources
- CVE List CVE-2023-35926
- GitHub Advisory GHSA-wg6p-jmpc-xjmr
- NVD CVE-2023-35926
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