FKIE_CVE-2026-63343

Vulnerability from fkie_nvd - Published: 2026-08-21 15:16 - Updated: 2026-10-15 19:10
Severity
9.9 (Critical) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Summary
Incus is a system container and virtual machine manager. Prior to version 7.3.0, a malicious image containing a `metadata.yaml` symlink pointing to an arbitrary host path allows an authenticated Incus user to read or overwrite any file on the host as root via the instance metadata API. The `exec-output` and `templates/` paths were patched in a prior release using `Lstat` rejection and `os.OpenRoot` confinement; `metadata.yaml` was not included in either patch and remains exploitable. Version 7.3.0 patches the issue.
References
security-advisories@github.comhttps://github.com/lxc/incus/security/advisories/GHSA-fmjx-5j3g-997p
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "incus",
          "vendor": "lxc",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 7.3.0"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Incus is a system container and virtual machine manager. Prior to version 7.3.0, a malicious image containing a `metadata.yaml` symlink pointing to an arbitrary host path allows an authenticated Incus user to read or overwrite any file on the host as root via the instance metadata API. The `exec-output` and `templates/` paths were patched in a prior release using `Lstat` rejection and `os.OpenRoot` confinement; `metadata.yaml` was not included in either patch and remains exploitable. Version 7.3.0 patches the issue."
    },
    {
      "lang": "es",
      "value": "Incus es un gestor de contenedores de sistema y m\u00e1quinas virtuales. Antes de la versi\u00f3n 7.3.0, una imagen maliciosa que contiene un enlace simb\u00f3lico \u0027metadata.yaml\u0027 que apunta a una ruta de host arbitraria permite a un usuario autenticado de Incus leer o sobrescribir cualquier archivo en el host como root a trav\u00e9s de la API de metadatos de la instancia. Las rutas \u0027exec-output\u0027 y \u0027templates/\u0027 fueron parcheadas en una versi\u00f3n anterior utilizando el rechazo de \u0027Lstat\u0027 y el confinamiento de \u0027os.OpenRoot\u0027; \u0027metadata.yaml\u0027 no se incluy\u00f3 en ninguno de los parches y sigue siendo explotable. La versi\u00f3n 7.3.0 parchea el problema."
    }
  ],
  "id": "CVE-2026-63343",
  "lastModified": "2026-10-15T19:10:00.173",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.9,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.1,
        "impactScore": 6.0,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-63343",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-08-21T21:00:14.696240Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-08-21T15:16:46.577",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/lxc/incus/security/advisories/GHSA-fmjx-5j3g-997p"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-73"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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