{"cve":"CVE-2026-24047","nvd":{"published":"2026-01-21T23:15:53.407","modified":"2026-06-17T10:22:31.057","status":"Deferred","description":"Backstage is an open framework for building developer portals, and @backstage/cli-common provides config loading functionality used by the backend and command line interface of Backstage. Prior to version 0.1.17, the `resolveSafeChildPath` utility function in `@backstage/backend-plugin-api`, which is used to prevent path traversal attacks, failed to properly validate symlink chains and dangling symlinks. An attacker could bypass the path validation via symlink chains (creating `link1 → link2 → /outside` where intermediate symlinks eventually resolve outside the allowed directory) and dangling symlinks (creating symlinks pointing to non-existent paths outside the base directory, which would later be created during file operations). This function is used by Scaffolder actions and other backend components to ensure file operations stay within designated directories. This vulnerability is fixed in `@backstage/backend-plugin-api` version 0.1.17. Users should upgrade to this version or later. Some workarounds are available. Run Backstage in a containerized environment with limited filesystem access and/or restrict template creation to trusted users.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N","score":6.3},"cwes":["CWE-59","CWE-61"],"references":["https://github.com/backstage/backstage/commit/ae4dd5d1572a4f639e1a466fd982656b50f8e692","https://github.com/backstage/backstage/security/advisories/GHSA-2p49-45hj-7mc9"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:21:16.563232421+00:00"},"epss":{"cve":"CVE-2026-24047","score":0.00534,"percentile":0.45074,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-2p49-45hj-7mc9","url":"https://osv.dev/vulnerability/GHSA-2p49-45hj-7mc9","summary":"@backstage/cli-common has a possible `resolveSafeChildPath` Symlink Chain Bypass","modified":"2026-02-03T03:10:16.981108Z","packages":[{"ecosystem":"npm","name":"@backstage/cli-common","purl":"pkg:npm/%40backstage/cli-common","ranges":["<0.1.17"],"fixed":["0.1.17"]}]}],"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."]}