Backstage: TechDocs arbitrary file read via mkdocs snippets

Backstage is an open framework for building developer portals. Prior to 1.15.4, the @backstage/plugin-techdocs-node package is affected by techdocs arbitrary file read via mkdocs snippets. Unsafe path resolution in TechDocs source tree handling allows an authenticated user who can register documentation sources to include content from outside the intended documentation boundary. Depending on deployment, this may expose files readable by the build process. This issue is fixed in version 1.15.4.

Problem type

Affected products

backstage

backstage

< 1.54.6 - AFFECTED

@backstage/plugin-techdocs-node

plugin-techdocs-node

< 1.15.4 - AFFECTED

References

https://github.com/backstage/backstage/security/advisories/GHSA-vmqh-7cj9-mvcj

https://github.com/backstage/backstage/security/advisories/GHSA-vmqh-7cj9-mvcj

x_refsource_CONFIRM

https://github.com/backstage/backstage/commit/911ca36f10e654c5517da029129230fc05a4f580

https://github.com/backstage/backstage/commit/911ca36f10e654c5517da029129230fc05a4f580

x_refsource_MISC

https://github.com/backstage/backstage/releases/tag/v1.54.6

https://github.com/backstage/backstage/releases/tag/v1.54.6

x_refsource_MISC

JSON source

https://cveawg.mitre.org/api/cve/CVE-2026-106507

Click to expand

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-106507",
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "dateUpdated": "2026-10-06T21:46:08.014Z",
    "dateReserved": "2026-10-06T18:46:47.766Z",
    "datePublished": "2026-10-06T21:46:08.014Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M",
        "dateUpdated": "2026-10-06T21:46:08.014Z"
      },
      "title": "Backstage: TechDocs arbitrary file read via mkdocs snippets",
      "descriptions": [
        {
          "lang": "en",
          "value": "Backstage is an open framework for building developer portals. Prior to 1.15.4, the @backstage/plugin-techdocs-node package is affected by techdocs arbitrary file read via mkdocs snippets. Unsafe path resolution in TechDocs source tree handling allows an authenticated user who can register documentation sources to include content from outside the intended documentation boundary. Depending on deployment, this may expose files readable by the build process. This issue is fixed in version 1.15.4."
        }
      ],
      "affected": [
        {
          "vendor": "backstage",
          "product": "backstage",
          "versions": [
            {
              "version": "< 1.54.6",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "@backstage/plugin-techdocs-node",
          "product": "plugin-techdocs-node",
          "versions": [
            {
              "version": "< 1.15.4",
              "status": "affected"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "CWE-59: Improper Link Resolution Before File Access ('Link Following')",
              "cweId": "CWE-59",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "CWE-61: UNIX Symbolic Link (Symlink) Following",
              "cweId": "CWE-61",
              "type": "CWE"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://github.com/backstage/backstage/security/advisories/GHSA-vmqh-7cj9-mvcj",
          "name": "https://github.com/backstage/backstage/security/advisories/GHSA-vmqh-7cj9-mvcj",
          "tags": [
            "x_refsource_CONFIRM"
          ]
        },
        {
          "url": "https://github.com/backstage/backstage/commit/911ca36f10e654c5517da029129230fc05a4f580",
          "name": "https://github.com/backstage/backstage/commit/911ca36f10e654c5517da029129230fc05a4f580",
          "tags": [
            "x_refsource_MISC"
          ]
        },
        {
          "url": "https://github.com/backstage/backstage/releases/tag/v1.54.6",
          "name": "https://github.com/backstage/backstage/releases/tag/v1.54.6",
          "tags": [
            "x_refsource_MISC"
          ]
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "version": "3.1",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N",
            "attackVector": "NETWORK",
            "attackComplexity": "HIGH",
            "privilegesRequired": "LOW",
            "userInteraction": "NONE",
            "scope": "UNCHANGED",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "availabilityImpact": "NONE",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM"
          }
        }
      ]
    }
  }
}