« Volver al listado

CVE-2026-72254

Estado: RecibidaAlta (7.5)—

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

netfilter: nft_fib: reject fib expression on the netdev egress hook

A fib expression in a netdev egress base chain dereferences nft_in(pkt), NULL on the transmit path, causing a NULL pointer dereference at eval. nft_fib_validate() masks the hook with NF_INET_* values, but netdev hook numbers are a separate enum that aliases them (NF_NETDEV_EGRESS == NF_INET_LOCAL_IN), so an egress chain passes validation and then faults.

Add nft_fib_netdev_validate() that limits each result/flag to the netdev hook where the device it reads exists: the input-device cases (OIF, OIFNAME, ADDRTYPE with F_IIF) to ingress, the output-device case (ADDRTYPE with F_OIF) to egress, ADDRTYPE with no device flag to both.

Leer descripción completaMostrar menos

Also restrict nft_fib_validate() to NFPROTO_IPV4/IPV6/INET so its NF_INET_* masks are not applied to another family's hooks.

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.

Inferido por reglas deterministas a partir del vector CVSS y la CWE. Solo orientativo.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Tecnologías afectadas (1)

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

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-72254",
  "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": "42df6e1d221dddc0f2acf2be37e68d553ad65f96",
              "lessThan": "4fee43759b489559a491f7c95f9bfa7a1d0c7a10",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "42df6e1d221dddc0f2acf2be37e68d553ad65f96",
              "lessThan": "568931f26af4727a51e8521f72efbc78d3b82410",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "42df6e1d221dddc0f2acf2be37e68d553ad65f96",
              "lessThan": "d01c913febead04a01a5f3a6374d1f45504dc523",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "42df6e1d221dddc0f2acf2be37e68d553ad65f96",
              "lessThan": "f68305267ebda7e839b5e8f77e8d77535a3d5a0f",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "42df6e1d221dddc0f2acf2be37e68d553ad65f96",
              "lessThan": "d07955dd34ecae17d35d8c7d0a273a3fba653a8c",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "net/netfilter/nft_fib.c",
            "net/netfilter/nft_fib_netdev.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.16"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "5.16",
              "versionType": "semver"
            },
            {
              "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": "7.1.5",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "net/netfilter/nft_fib.c",
            "net/netfilter/nft_fib_netdev.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-08-15T06:21:52.910",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/4fee43759b489559a491f7c95f9bfa7a1d0c7a10",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/568931f26af4727a51e8521f72efbc78d3b82410",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d01c913febead04a01a5f3a6374d1f45504dc523",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d07955dd34ecae17d35d8c7d0a273a3fba653a8c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f68305267ebda7e839b5e8f77e8d77535a3d5a0f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nft_fib: reject fib expression on the netdev egress hook\n\nA fib expression in a netdev egress base chain dereferences nft_in(pkt),\nNULL on the transmit path, causing a NULL pointer dereference at eval.\nnft_fib_validate() masks the hook with NF_INET_* values, but netdev hook\nnumbers are a separate enum that aliases them (NF_NETDEV_EGRESS ==\nNF_INET_LOCAL_IN), so an egress chain passes validation and then faults.\n\nAdd nft_fib_netdev_validate() that limits each result/flag to the netdev\nhook where the device it reads exists: the input-device cases (OIF,\nOIFNAME, ADDRTYPE with F_IIF) to ingress, the output-device case (ADDRTYPE\nwith F_OIF) to egress, ADDRTYPE with no device flag to both. Also restrict\nnft_fib_validate() to NFPROTO_IPV4/IPV6/INET so its NF_INET_* masks are\nnot applied to another family's hooks."
    }
  ],
  "lastModified": "2026-08-17T06:18:27.610",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}