Backstage: Improper validation of TechDocs MkDocs configuration

{
  "id": "be14c1ce518f6c72ed652414d363c4a8d73d5f0be9b4bb4ec902a9cb6dab0e0b",
  "url": "https://osv.dev/vulnerability/GHSA-qmw3-745m-w99g",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Backstage: Improper validation of TechDocs MkDocs configuration",
    "summary": "### Impact An attacker who can provide configuration to a TechDocs build may execute code in the generator runtime. Impact is greatest when documentation generation runs with backend credentials or host access. ### Patches Patched in `@backstage/plugin-techdocs-node` version `1.15.4`. ### Workarounds Use external TechDocs generation in an isolated environment without sensitive credentials or host access. Restrict and review changes to documentation configuration before generation.",
    "evidence": "osv:GHSA-qmw3-745m-w99g",
    "products": [
      {
        "name": {
          "value": "@backstage/plugin-techdocs-node",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "1.15.4",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "GHSA-qmw3-745m-w99g",
      "aliases": [
        "CVE-2026-106558",
        "GHSA-qmw3-745m-w99g"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "1.15.4"
                }
              ]
            }
          ],
          "package": {
            "name": "@backstage/plugin-techdocs-node",
            "purl": "pkg:npm/%40backstage/plugin-techdocs-node",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-qmw3-745m-w99g/GHSA-qmw3-745m-w99g.json"
          }
        }
      ],
      "modified": "2026-10-07T18:15:12.165363848Z",
      "provider": "osv",
      "references": [
        "https://github.com/backstage/backstage/security/advisories/GHSA-qmw3-745m-w99g",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-106558",
        "https://github.com/backstage/backstage/commit/32723a0fe4e12ed80535fc65d5331765c55aa91b",
        "https://github.com/backstage/backstage/commit/944edb51c8524d3664b18f2d57ba101b1c93b709",
        "https://github.com/backstage/backstage/commit/f18e9abcc6051491862b15e4fc60e69f8d52310c",
        "https://github.com/backstage/backstage",
        "https://github.com/backstage/backstage/releases/tag/v1.50.7",
        "https://github.com/backstage/backstage/releases/tag/v1.54.9",
        "https://github.com/backstage/backstage/releases/tag/v1.55.2"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-502"
        ],
        "severity": "HIGH",
        "github_reviewed": true,
        "nvd_published_at": "2026-10-07T15:17:15Z",
        "github_reviewed_at": "2026-10-07T18:03:12Z"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-106558",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/database_specific/severity"
  },
  "source_id": "core-osv",
  "document_id": 97160,
  "published_at": "2026-10-07T18:03:12+00:00"
}