FKIE_CVE-2026-88064

Vulnerability from fkie_nvd - Published: 2026-09-16 15:18 - Updated: 2026-09-30 17:43
Severity
8.8 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
Backstage is an open framework for building developer portals. Prior to 1.14.6 and from 1.15.0 until 1.15.4, the @backstage/plugin-techdocs-node package insufficiently validates mkdocs.yml supplied by an authenticated user who can register or modify a TechDocs source. Unsafe Python YAML tags, markdown_extensions names and configuration, theme options, and extra_templates values can reach the documentation generator and cause unintended code execution. The resulting impact is limited to the files, credentials, network access, and other resources available to the TechDocs backend or build container. This issue is fixed in versions 1.14.6 and 1.15.4.
References
security-advisories@github.comhttps://github.com/backstage/backstage/commit/017ace52d9b327ededc6704cf17799c875ae0f29
security-advisories@github.comhttps://github.com/backstage/backstage/commit/02cd7cdbb18b687446277b5602adaee7f1d53cbb
security-advisories@github.comhttps://github.com/backstage/backstage/commit/25125ee727a3de3418a8fa6a9e458cd5b73ecf26
security-advisories@github.comhttps://github.com/backstage/backstage/commit/a7d995f11a5d27f0efbdbe8bb6c21b06988c79c9
security-advisories@github.comhttps://github.com/backstage/backstage/commit/a900a9953c8f7ad3ba1906d1d257725a9996cc9d
security-advisories@github.comhttps://github.com/backstage/backstage/releases/tag/v1.50.5
security-advisories@github.comhttps://github.com/backstage/backstage/releases/tag/v1.54.6
security-advisories@github.comhttps://github.com/backstage/backstage/security/advisories/GHSA-292q-8mf5-h6g3
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "backstage",
          "vendor": "backstage",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.14.6"
            },
            {
              "status": "affected",
              "version": "\u003e= 1.15.0, \u003c 1.15.4"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Backstage is an open framework for building developer portals. Prior to 1.14.6 and from 1.15.0 until 1.15.4, the @backstage/plugin-techdocs-node package insufficiently validates mkdocs.yml supplied by an authenticated user who can register or modify a TechDocs source. Unsafe Python YAML tags, markdown_extensions names and configuration, theme options, and extra_templates values can reach the documentation generator and cause unintended code execution. The resulting impact is limited to the files, credentials, network access, and other resources available to the TechDocs backend or build container. This issue is fixed in versions 1.14.6 and 1.15.4."
    }
  ],
  "id": "CVE-2026-88064",
  "lastModified": "2026-09-30T17:43:24.057",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-88064",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-16T15:46:28.697895Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-16T15:18:04.297",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/commit/017ace52d9b327ededc6704cf17799c875ae0f29"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/commit/02cd7cdbb18b687446277b5602adaee7f1d53cbb"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/commit/25125ee727a3de3418a8fa6a9e458cd5b73ecf26"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/commit/a7d995f11a5d27f0efbdbe8bb6c21b06988c79c9"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/commit/a900a9953c8f7ad3ba1906d1d257725a9996cc9d"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/releases/tag/v1.50.5"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/releases/tag/v1.54.6"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/security/advisories/GHSA-292q-8mf5-h6g3"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-20"
        },
        {
          "lang": "en",
          "value": "CWE-1336"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.