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CVE-2026-98647

Estado: RecibidaSin puntuar—
Gravedad—Sin puntuar
Probabilidad de explotación0.17 %mayor que el 6 % de las CVE
Explotación activaNono figura en el catálogo de CISA
Exploit públicoNo conocidosin código público localizado

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad:

bpf: Corrige la división por cero en btf_struct_walk()

Cuando un acceso supera el final de la estructura y el último miembro es un array flexible, btf_struct_walk() reduce el desplazamiento a un único elemento con (off - moff) % t->size, pero nunca comprueba que el tipo del elemento tenga tamaño.

BTF admite una estructura vacía, de modo que esto en el BTF del programa

divide por cero en el momento de cargar el programa. Para llegar hasta ahí hace falta un PTR_TO_BTF_ID que no sea MEM_ALLOC, por ejemplo una lectura simple de un kptr local almacenado en un mapa desde un programa sleepable.

Leer descripción completaMostrar menos

Rechaza un tipo de elemento de tamaño cero. La ruta de los arrays de tamaño fijo de la misma función ya descarta este caso:

btf_struct_walk() ... /* skip empty array */ if (moff == mtrue_end) continue;

Detalles técnicos trazas, registros y código del informe original
	/* event could be empty */
	struct event {
 #ifdef HAVE_TIMESTAMP
		__u64 ts;
 #endif
	};

	struct batch {
		int nr;
		struct event events[];
	};

Oops: divide error: 0000 [#1] SMP KASAN PTI
RIP: 0010:btf_struct_walk+0x53f/0x1570
Call Trace:
 <TASK>
 btf_struct_access+0x42a/0xcd0
 check_ptr_to_btf_access+0x4dc/0x1160
 check_mem_access+0x3a45/0x8740
 check_load_mem+0x36a/0xd10
 do_check_common+0x3ef0/0xb210
 bpf_check+0x6d3b/0x8580
 bpf_prog_load+0xf7c/0x2720
 __sys_bpf+0xa83/0x3690
 __x64_sys_bpf+0xc7/0x150
 x64_sys_call+0x1f3f/0x27e0
 do_syscall_64+0xe5/0x610
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
 </TASK>

		msize /= total_nelems;

Traducción automática del texto original de NVD (en inglés).

CVSS

NVD no ha asignado puntuación CVSS a esta CVE (habitual desde el cambio de política de abril de 2026).

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días
0.17 %
Percentil entre todas las CVEs puntuadas
6
Fecha de la puntuación
20/10/2026

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).

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

Mostrar las 7 referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-98647",
  "cveTags": [],
  "metrics": {},
  "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": "9c5f8a1008a121e4c6b24af211034e24b0b63081",
              "lessThan": "1ea3820937f8022e044c41c6e95c84b02741b45f",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9c5f8a1008a121e4c6b24af211034e24b0b63081",
              "lessThan": "172756f02663ad45c889c001c1a8cb4082a01a05",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9c5f8a1008a121e4c6b24af211034e24b0b63081",
              "lessThan": "934e9ba9f8d05656a48624710be67ca4dc8482e6",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9c5f8a1008a121e4c6b24af211034e24b0b63081",
              "lessThan": "63af086cb5fa6f72fd924f86bea4c2194da663a2",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9c5f8a1008a121e4c6b24af211034e24b0b63081",
              "lessThan": "8eb4cd72daad3a9ee63d2281bbdd16ce6d9406b1",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9c5f8a1008a121e4c6b24af211034e24b0b63081",
              "lessThan": "b8fa56722e9c43bcd59c51fe4c7edd5f4158a11b",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9c5f8a1008a121e4c6b24af211034e24b0b63081",
              "lessThan": "b0b3dc66529676228cb938cbcad66920f735c223",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "kernel/bpf/btf.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.8"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "5.8",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.15.222",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.189",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.158",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.12.112",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.55",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.2.9",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "kernel/bpf/btf.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-10-18T16:17:17.980",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/172756f02663ad45c889c001c1a8cb4082a01a05",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/1ea3820937f8022e044c41c6e95c84b02741b45f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/63af086cb5fa6f72fd924f86bea4c2194da663a2",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8eb4cd72daad3a9ee63d2281bbdd16ce6d9406b1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/934e9ba9f8d05656a48624710be67ca4dc8482e6",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b0b3dc66529676228cb938cbcad66920f735c223",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b8fa56722e9c43bcd59c51fe4c7edd5f4158a11b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix divide-by-zero in btf_struct_walk()\n\nWhen an access goes past the struct and the last member is a flexible\narray, btf_struct_walk() folds the offset back into a single element with\n(off - moff) % t->size, but never checks that the element type has a size.\n\nBTF takes an empty struct, so this in program BTF\n\n\t/* event could be empty */\n\tstruct event {\n #ifdef HAVE_TIMESTAMP\n\t\t__u64 ts;\n #endif\n\t};\n\n\tstruct batch {\n\t\tint nr;\n\t\tstruct event events[];\n\t};\n\ndivides by zero at prog load time. Getting there needs a PTR_TO_BTF_ID that\nis not MEM_ALLOC, e.g. a plain read of a local kptr stashed in a map from a\nsleepable program.\n\nOops: divide error: 0000 [#1] SMP KASAN PTI\nRIP: 0010:btf_struct_walk+0x53f/0x1570\nCall Trace:\n <TASK>\n btf_struct_access+0x42a/0xcd0\n check_ptr_to_btf_access+0x4dc/0x1160\n check_mem_access+0x3a45/0x8740\n check_load_mem+0x36a/0xd10\n do_check_common+0x3ef0/0xb210\n bpf_check+0x6d3b/0x8580\n bpf_prog_load+0xf7c/0x2720\n __sys_bpf+0xa83/0x3690\n __x64_sys_bpf+0xc7/0x150\n x64_sys_call+0x1f3f/0x27e0\n do_syscall_64+0xe5/0x610\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n </TASK>\n\nReject a zero-sized element type. The fixed array path in the same function\nalready bails out on the same thing:\n\n\tbtf_struct_walk()\n\t...\n\t\t/* skip empty array */\n\t\tif (moff == mtrue_end)\n\t\t\tcontinue;\n\n\t\tmsize /= total_nelems;"
    }
  ],
  "lastModified": "2026-10-19T10:19:29.113",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}