GHSA-q2x5-4xjx-c6p9

Suggest an improvement
Source
https://github.com/advisories/GHSA-q2x5-4xjx-c6p9
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-q2x5-4xjx-c6p9/GHSA-q2x5-4xjx-c6p9.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-q2x5-4xjx-c6p9
Aliases
Published
2026-01-21T22:49:37Z
Modified
2026-02-03T03:10:27Z
Severity
  • 3.5 (Low) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N CVSS Calculator
Summary
Backstage has a Possible SSRF when reading from allowed URL's in `backend.reading.allow`
Details

Impact

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.

Patches

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.

Workarounds

  • 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
  • Use network-level controls to block access from Backstage to sensitive internal endpoints

References

Database specific 
{
    "cwe_ids":  [
        "CWE-918"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-01-21T22:49:37Z",
    "nvd_published_at":  "2026-01-21T23:15:53Z",
    "severity":  "LOW"
}
References

Affected packages

npm / @backstage/backend-defaults

Package

Name
@backstage/backend-defaults
View open source insights on deps.dev
Purl
pkg:npm/%40backstage/backend-defaults

Affected ranges

Type
SEMVER
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
0.12.2

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-q2x5-4xjx-c6p9/GHSA-q2x5-4xjx-c6p9.json"

npm / @backstage/backend-defaults

Package

Name
@backstage/backend-defaults
View open source insights on deps.dev
Purl
pkg:npm/%40backstage/backend-defaults

Affected ranges

Type
SEMVER
Events
Introduced
0.13.0
Fixed
0.13.2

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-q2x5-4xjx-c6p9/GHSA-q2x5-4xjx-c6p9.json"

npm / @backstage/backend-defaults

Package

Name
@backstage/backend-defaults
View open source insights on deps.dev
Purl
pkg:npm/%40backstage/backend-defaults

Affected ranges

Type
SEMVER
Events
Introduced
0.14.0
Fixed
0.14.1

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-q2x5-4xjx-c6p9/GHSA-q2x5-4xjx-c6p9.json"