{"cve":"CVE-2026-24048","nvd":{"published":"2026-01-21T23:15:53.580","modified":"2026-06-17T10:22:31.160","status":"Analyzed","description":"Backstage is an open framework for building developer portals, and @backstage/backend-defaults provides the default implementations and setup for a standard Backstage backend app. Prior to versions 0.12.2, 0.13.2, 0.14.1, and 0.15.0, the `FetchUrlReader` component, used by the catalog and other plugins to fetch content from URLs, followed HTTP redirects automatically. This allowed an attacker who controls a host listed in `backend.reading.allow` to redirect requests to internal or sensitive URLs that are not on the allowlist, bypassing the URL allowlist security control. This is a Server-Side Request Forgery (SSRF) vulnerability that could allow access to internal resources, but it does not allow attackers to include additional request headers. This vulnerability is fixed in `@backstage/backend-defaults` version 0.12.2, 0.13.2, 0.14.1, and 0.15.0. Users should upgrade to this version or later. Some workarounds are available. Restrict `backend.reading.allow` to only trusted hosts that you control and that do not issue redirects, ensure allowed hosts do not have open redirect vulnerabilities, and/or use network-level controls to block access from Backstage to sensitive internal endpoints.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","score":3.7},"cwes":["CWE-918"],"references":["https://github.com/backstage/backstage/commit/27f9061d24affd1b9212fe0abd476bfc3fbaedcb","https://github.com/backstage/backstage/security/advisories/GHSA-q2x5-4xjx-c6p9"],"products":["linuxfoundation:backstage\\/backend_defaults"],"source":"nvd","synced_at":"2026-10-19T22:21:16.563232421+00:00"},"epss":{"cve":"CVE-2026-24048","score":0.00235,"percentile":0.14561,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-q2x5-4xjx-c6p9","url":"https://osv.dev/vulnerability/GHSA-q2x5-4xjx-c6p9","summary":"Backstage has a Possible SSRF when reading from allowed URL's in `backend.reading.allow`","modified":"2026-02-03T03:10:27.142022Z","packages":[{"ecosystem":"npm","name":"@backstage/backend-defaults","purl":"pkg:npm/%40backstage/backend-defaults","ranges":["<0.12.2"],"fixed":["0.12.2"]},{"ecosystem":"npm","name":"@backstage/backend-defaults","purl":"pkg:npm/%40backstage/backend-defaults","ranges":[">=0.13.0 <0.13.2"],"fixed":["0.13.2"]},{"ecosystem":"npm","name":"@backstage/backend-defaults","purl":"pkg:npm/%40backstage/backend-defaults","ranges":[">=0.14.0 <0.14.1"],"fixed":["0.14.1"]}]}],"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."]}