{"cve":"CVE-2021-43783","nvd":{"published":"2021-11-29T20:15:08.077","modified":"2026-06-17T04:11:25.860","status":"Undergoing Analysis","description":"@backstage/plugin-scaffolder-backend is the backend for the default Backstage software templates. In affected versions a malicious actor with write access to a registered scaffolder template is able to manipulate the template in a way that writes files to arbitrary paths on the scaffolder-backend host instance. This vulnerability can in some situation also be exploited through user input when executing a template, meaning you do not need write access to the templates. This method will not allow the attacker to control the contents of the injected file however, unless the template is also crafted in a specific way that gives control of the file contents. This vulnerability is fixed in version `0.15.14` of the `@backstage/plugin-scaffolder-backend`. This attack is mitigated by restricting access and requiring reviews when registering or modifying scaffolder templates.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:L","score":8.5},"cwes":["CWE-22"],"references":["https://github.com/backstage/backstage/commit/f9352ab606367cd9efc6ff048915c70ed3013b7f","https://github.com/backstage/backstage/security/advisories/GHSA-mg3m-f475-28hv","https://github.com/backstage/backstage/commit/f9352ab606367cd9efc6ff048915c70ed3013b7f","https://github.com/backstage/backstage/security/advisories/GHSA-mg3m-f475-28hv"],"products":["linuxfoundation:backstage"],"source":"nvd","synced_at":"2026-10-19T21:25:41.256909649+00:00"},"epss":{"cve":"CVE-2021-43783","score":0.01246,"percentile":0.69315,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-mg3m-f475-28hv","url":"https://osv.dev/vulnerability/GHSA-mg3m-f475-28hv","summary":"Path Traversal in @backstage/plugin-scaffolder-backend","modified":"2026-07-08T06:53:07.906096860Z","packages":[{"ecosystem":"npm","name":"@backstage/plugin-scaffolder-backend","purl":"pkg:npm/%40backstage/plugin-scaffolder-backend","ranges":["<0.15.14"],"fixed":["0.15.14"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}