{"id":"CVE-2023-35926","aliases":["GHSA-wg6p-jmpc-xjmr"],"url":"https://o3.security/vulnerability/CVE-2023-35926","summary":"Insecure sandbox in Backstage Scaffolder plugin","details":"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.\n\n### Impact\n\nA 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.\n\n### Patches\n\nThis is vulnerability is fixed in version 1.15.0 of `@backstage/plugin-scaffolder-backend`.\n\n### Workarounds\n\nNote 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.","published":"2023-06-22T13:29:03.361Z","modified":"2026-10-28T02:30:31.986545031Z","cvss":{"score":8,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"@backstage/plugin-scaffolder-backend","fixedVersion":"1.15.0"}],"fix":{"url":"https://github.com/backstage/backstage/commit/fb7375507d56faedcb7bb3665480070593c8949a","label":"backstage/backstage@fb73755"},"references":[{"type":"WEB","url":"https://github.com/backstage/backstage/releases/tag/v1.15.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/35xxx/CVE-2023-35926.json"},{"type":"ADVISORY","url":"https://github.com/backstage/backstage/security/advisories/GHSA-wg6p-jmpc-xjmr"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-35926"},{"type":"FIX","url":"https://github.com/backstage/backstage/commit/fb7375507d56faedcb7bb3665480070593c8949a"},{"type":"PACKAGE","url":"https://github.com/backstage/backstage"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T02:30:31.986545031Z"}}