Backstage: Improper preservation of access restrictions during service credential delegation

{
  "id": "215aa5a96bcfe26ec5b98af930206898c7406ed8c1cf0effa8d29e4452fe11f9",
  "url": "https://osv.dev/vulnerability/GHSA-cq7v-rfgc-5c7v",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Backstage: Improper preservation of access restrictions during service credential delegation",
    "summary": "### Impact An external service credential configured with access restrictions (e.g., read-only) could bypass those restrictions by routing requests through plugin delegation paths. This could allow a restricted service to perform operations beyond its intended scope, including write operations on plugins it was restricted to read-only access for. ### Patches Patched in `@backstage/backend-defaults` version `0.17.8` ### Workarounds If you're unable to upgrade immediately: - If practical, replace restricted credentials with separate, purpose-specific unrestricted credentials scoped to trusted consumers. - Restrict network-level access to Backstage backend API endpoints to trusted callers only.",
    "evidence": "osv:GHSA-cq7v-rfgc-5c7v",
    "products": [
      {
        "name": {
          "value": "@backstage/backend-defaults",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "0.17.8",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "GHSA-cq7v-rfgc-5c7v",
      "aliases": [
        "CVE-2026-106492",
        "GHSA-cq7v-rfgc-5c7v"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "0.17.8"
                }
              ]
            }
          ],
          "package": {
            "name": "@backstage/backend-defaults",
            "purl": "pkg:npm/%40backstage/backend-defaults",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-cq7v-rfgc-5c7v/GHSA-cq7v-rfgc-5c7v.json"
          }
        }
      ],
      "modified": "2026-10-07T18:15:11.766063944Z",
      "provider": "osv",
      "references": [
        "https://github.com/backstage/backstage/security/advisories/GHSA-cq7v-rfgc-5c7v",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-106492",
        "https://github.com/backstage/backstage/commit/40346245c53e1bf26dee56601e95c5c4ab9cc124",
        "https://github.com/backstage/backstage/commit/bc80ffdafbc92ff7b8c72347eace13cb8688fd33",
        "https://github.com/backstage/backstage",
        "https://github.com/backstage/backstage/releases/tag/v1.49.6",
        "https://github.com/backstage/backstage/releases/tag/v1.54.6"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-269",
          "CWE-863"
        ],
        "severity": "HIGH",
        "github_reviewed": true,
        "nvd_published_at": "2026-10-06T21:17:18Z",
        "github_reviewed_at": "2026-10-07T17:59:43Z"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-106492",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/database_specific/severity"
  },
  "source_id": "core-osv",
  "document_id": 97158,
  "published_at": "2026-10-07T17:59:43+00:00"
}