Server-side Request Forgery (SSRF) Affecting @backstage/backend-defaults package, versions <0.12.2>=0.13.0-next.0 <0.13.2>=0.14.0-next.0 <0.14.1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published23 Jan 2026
- disclosed21 Jan 2026
- creditUnknown
Introduced: 21 Jan 2026
CVE-2026-24048 (opens in a new tab)How to fix?
Upgrade @backstage/backend-defaults to version 0.12.2, 0.13.2, 0.14.1 or higher.
Overview
@backstage/backend-defaults is a Backend defaults used by Backstage backend apps
Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via the FetchUrlReader component that automatically follows HTTP redirects. An attacker can access internal or sensitive resources by controlling a host listed in backend.reading.allow and issuing HTTP redirects to URLs that are not on the allowlist, thereby bypassing security controls.
Workaround
This vulnerability can be mitigated by restricting backend.reading.allow to only trusted hosts that you control and that do not issue redirects, ensuring allowed hosts do not have open redirect vulnerabilities, and using network-level controls to block access from Backstage to sensitive internal endpoints.