« Volver al listado

CVE-2026-85185

Estado: AplazadaCrítica (9.6)—

Path traversal in the btrfs storage driver in Canonical LXD versions 4.0.2 and later (fixed in 4.0.14, 5.0.10, 5.21.8 and 6.10) on Linux allows an authenticated client with permission to create instances in a project to delete arbitrary files on the host as root. On hosts whose root filesystem is btrfs, the client can also place attacker-controlled content at arbitrary host paths, leading to full host compromise. The client does this with a crafted subvolume path containing ../ sequences, sent in either of two ways: in the optimized_header.yaml of an optimized btrfs backup, or in the btrfs migration header sent by a malicious migration source.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

Cliente autenticado con permisos locales en LXD explota path traversal (CWE-22) en btrfs para escribir contenido controlado en rutas arbitrarias del host como root (manipulación/eliminación de archivos), logrando compromiso total.

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Vulnerability ScanningThreat Intelligence ProgramPrivileged Account ManagementNetwork SegmentationEncrypt Sensitive InformationDisable or Remove Feature or Program

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Canonical — LXDAI

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-85185",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-85185",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-09-28T13:55:28.506443Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "security@ubuntu.com",
        "cvssData": {
          "scope": "CHANGED",
          "version": "3.1",
          "baseScore": 9.6,
          "attackVector": "NETWORK",
          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 5.8,
        "exploitabilityScore": 3.1
      }
    ]
  },
  "affected": [
    {
      "source": "security@ubuntu.com",
      "affectedData": [
        {
          "repo": "https://github.com/canonical/lxd",
          "vendor": "Canonical",
          "product": "LXD",
          "versions": [
            {
              "status": "affected",
              "version": "4.0.2",
              "lessThan": "4.0.14",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "5.0.0",
              "lessThan": "5.0.10",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "5.21.0",
              "lessThan": "5.21.8",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "6.0",
              "lessThan": "6.10",
              "versionType": "semver"
            }
          ],
          "platforms": [
            "Linux"
          ],
          "packageName": "LXD",
          "defaultStatus": "unaffected"
        }
      ]
    }
  ],
  "published": "2026-09-28T14:17:20.130",
  "references": [
    {
      "url": "https://github.com/canonical/lxd/security/advisories/GHSA-27q7-qwhm-c34p",
      "source": "security@ubuntu.com"
    }
  ],
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "security@ubuntu.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-22"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Path traversal in the btrfs storage driver in Canonical LXD versions 4.0.2 and later (fixed in 4.0.14, 5.0.10, 5.21.8 and 6.10) on Linux allows an authenticated client with permission to create instances in a project to delete arbitrary files on the host as root. On hosts whose root filesystem is btrfs, the client can also place attacker-controlled content at arbitrary host paths, leading to full host compromise. The client does this with a crafted subvolume path containing ../ sequences, sent in either of two ways: in the optimized_header.yaml of an optimized btrfs backup, or in the btrfs migration header sent by a malicious migration source."
    }
  ],
  "lastModified": "2026-09-28T17:17:51.013",
  "sourceIdentifier": "security@ubuntu.com"
}