FKIE_CVE-2026-106558

Vulnerability from fkie_nvd - Published: 2026-10-07 15:17 - Updated: 2026-10-07 15:52
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 1.14.8, 1.15.6, and 2.0.1, the @backstage/plugin-techdocs-node package improperly validated mapping-style markdown_extensions configuration. An authenticated attacker who can register or influence an SCM-backed documentation source may bypass TechDocs sanitization and cause Python objects to be imported and instantiated in the generator runtime, leading to arbitrary code execution. Earlier fixes in versions 1.14.6 and 1.15.4 did not fully address the supported mapping representation of markdown_extensions. Impact is greatest when documentation generation runs with backend credentials, filesystem access, or internal network access. This issue is fixed in versions 1.14.8, 1.15.6, and 2.0.1.
References
security-advisories@github.comhttps://github.com/backstage/backstage/commit/32723a0fe4e12ed80535fc65d5331765c55aa91b
security-advisories@github.comhttps://github.com/backstage/backstage/commit/944edb51c8524d3664b18f2d57ba101b1c93b709
security-advisories@github.comhttps://github.com/backstage/backstage/commit/f18e9abcc6051491862b15e4fc60e69f8d52310c
security-advisories@github.comhttps://github.com/backstage/backstage/releases/tag/v1.50.7
security-advisories@github.comhttps://github.com/backstage/backstage/releases/tag/v1.54.9
security-advisories@github.comhttps://github.com/backstage/backstage/releases/tag/v1.55.2
security-advisories@github.comhttps://github.com/backstage/backstage/security/advisories/GHSA-qmw3-745m-w99g
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "backstage",
          "vendor": "backstage",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.50.7"
            },
            {
              "status": "affected",
              "version": "\u003e= 1.51.0-next.0, \u003c 1.54.9"
            },
            {
              "status": "affected",
              "version": "\u003e= 1.55.0-next.0, \u003c 1.55.2"
            }
          ]
        },
        {
          "product": "plugin-techdocs-node",
          "vendor": "@backstage",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.14.8"
            },
            {
              "status": "affected",
              "version": "\u003e= 1.15.0, \u003c 1.15.6"
            },
            {
              "status": "affected",
              "version": "\u003e= 2.0.0, \u003c 2.0.1"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Backstage is an open framework for building developer portals. Prior to 1.14.8, 1.15.6, and 2.0.1, the @backstage/plugin-techdocs-node package improperly validated mapping-style markdown_extensions configuration. An authenticated attacker who can register or influence an SCM-backed documentation source may bypass TechDocs sanitization and cause Python objects to be imported and instantiated in the generator runtime, leading to arbitrary code execution. Earlier fixes in versions 1.14.6 and 1.15.4 did not fully address the supported mapping representation of markdown_extensions. Impact is greatest when documentation generation runs with backend credentials, filesystem access, or internal network access. This issue is fixed in versions 1.14.8, 1.15.6, and 2.0.1."
    }
  ],
  "id": "CVE-2026-106558",
  "lastModified": "2026-10-07T15:52:18.453",
  "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"
      }
    ]
  },
  "published": "2026-10-07T15:17:15.713",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/commit/32723a0fe4e12ed80535fc65d5331765c55aa91b"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/commit/944edb51c8524d3664b18f2d57ba101b1c93b709"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/commit/f18e9abcc6051491862b15e4fc60e69f8d52310c"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/releases/tag/v1.50.7"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/releases/tag/v1.54.9"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/releases/tag/v1.55.2"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/backstage/backstage/security/advisories/GHSA-qmw3-745m-w99g"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-502"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}



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