« Volver al listado

CVE-2026-68299

Estado: RecibidaAlta (7.5)—

In the Linux kernel, the following vulnerability has been resolved:

vmxnet3: fix BUG_ON in vmxnet3_get_hdr_len() for Geneve packets

vmxnet3_get_hdr_len() assumes gdesc->rcd.v4/v6/tcp always describe the outer header, but for a Geneve-encapsulated packet the device can set them based on the inner header instead, signalled by the VMXNET3_RCD_HDR_INNER_SHIFT bit in the completion descriptor. Since the function never skips the outer encapsulation, this mismatch triggers:

Check VMXNET3_RCD_HDR_INNER_SHIFT up front and bail out, since the function cannot locate the inner header it would need to parse. Also convert the remaining BUG_ON()s in this function to return 0 defensively.

Detalles técnicos trazas, registros y código del informe original
- BUG_ON(hdr.ipv4->protocol != IPPROTO_TCP), because the outer
  protocol is UDP (Geneve), not TCP.
- BUG_ON(hdr.eth->h_proto != ...), when the tunnel's outer and inner
  IP versions differ (e.g. outer IPv6/inner IPv4 or vice versa).

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.

Vulnerabilidad en controlador de red (vmxnet3) accesible vía paquetes Geneve en red sin autenticación (AV:N, PR:N, UI:N). Causa panic/BUG_ON denegando servicio del kernel.

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

Filter Network TrafficVulnerability ScanningPrivileged Account ManagementNetwork SegmentationLimit Access to Resource Over NetworkApplication Isolation and Sandboxing

Tecnologías afectadas (1)

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

Linux — Linux KernelAI

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-68299",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.5,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 3.9
      }
    ]
  },
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc",
              "lessThan": "2ddf51fcb6dd7d55ceef38e2e1a5ab2ab7fd47b0",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc",
              "lessThan": "fbab6b73cc086e32698c86e43d1b16bf17d24c36",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc",
              "lessThan": "28e382646417c7e2be9c9a7079eddf627ff52b90",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc",
              "lessThan": "667b6e52048eaf4dbcf1707ed87ffd44abb9cb38",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc",
              "lessThan": "28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc",
              "lessThan": "4fdb0f162ccdbe9626863b10003855703253fa29",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc",
              "lessThan": "b28596baf87e25a078789f1c05817c8a3bf71257",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc",
              "lessThan": "34a71f5361fc3adb5b7138da78750b0d535a8252",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "drivers/net/vmxnet3/vmxnet3_drv.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.2"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "4.2",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.10.265",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.216",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.183",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.148",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.12.101",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "drivers/net/vmxnet3/vmxnet3_drv.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-08-10T13:20:19.440",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/28e382646417c7e2be9c9a7079eddf627ff52b90",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2ddf51fcb6dd7d55ceef38e2e1a5ab2ab7fd47b0",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/34a71f5361fc3adb5b7138da78750b0d535a8252",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4fdb0f162ccdbe9626863b10003855703253fa29",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/667b6e52048eaf4dbcf1707ed87ffd44abb9cb38",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b28596baf87e25a078789f1c05817c8a3bf71257",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/fbab6b73cc086e32698c86e43d1b16bf17d24c36",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvmxnet3: fix BUG_ON in vmxnet3_get_hdr_len() for Geneve packets\n\nvmxnet3_get_hdr_len() assumes gdesc->rcd.v4/v6/tcp always describe the\nouter header, but for a Geneve-encapsulated packet the device can set\nthem based on the inner header instead, signalled by the\nVMXNET3_RCD_HDR_INNER_SHIFT bit in the completion descriptor. Since the\nfunction never skips the outer encapsulation, this mismatch triggers:\n\n- BUG_ON(hdr.ipv4->protocol != IPPROTO_TCP), because the outer\n  protocol is UDP (Geneve), not TCP.\n- BUG_ON(hdr.eth->h_proto != ...), when the tunnel's outer and inner\n  IP versions differ (e.g. outer IPv6/inner IPv4 or vice versa).\n\nCheck VMXNET3_RCD_HDR_INNER_SHIFT up front and bail out, since the\nfunction cannot locate the inner header it would need to parse. Also\nconvert the remaining BUG_ON()s in this function to return 0\ndefensively."
    }
  ],
  "lastModified": "2026-08-19T17:20:41.040",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}