Backstage has a Possible SSRF when reading from allowed URL’s in `backend.reading.allow`_CVE-2026-24048

{
    "lastseen": "",
    "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.",
    "published": "2026-01-21T22:51:44.015Z",
    "modified": "2026-01-22T16:48:55.954Z",
    "type": "cve",
    "title": "Backstage has a Possible SSRF when reading from allowed URL's in `backend.reading.allow`",
    "source": "GitHub_M",
    "references": "https://github.com/backstage/backstage/security/advisories/GHSA-q2x5-4xjx-c6p9\nhttps://github.com/backstage/backstage/commit/27f9061d24affd1b9212fe0abd476bfc3fbaedcb",
    "id": "CVE-2026-24048",
    "bulletinFamily": "",
    "cwe": [
        "CWE-918"
    ],
    "cvelist": null,
    "sourceData": "backstage backstage < 0.12.2\nbackstage backstage >= 0.13.0, < 0.13.2\nbackstage backstage >= 0.14.0, < 0.14.1",
    "sourceHref": "",
    "cvss": {
        "score": 3.5,
        "severity": "LOW",
        "vector": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N",
        "version": "3.1"
    },
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    "href": "",
    "category_name": "CVE",
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    "product": "backstage",
    "version": "< 0.12.2",
    "vendor": "backstage",
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