CVE-2026-43186

Estado: AnalizadaCrítica (9.8)—

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

ipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data()

On the receive path, __ioam6_fill_trace_data() uses trace->nodelen to decide how much data to write for each node. It trusts this field as-is from the incoming packet, with no consistency check against trace->type (the 24-bit field that tells which data items are present). A crafted packet can set nodelen=0 while setting type bits 0-21, causing the function to write ~100 bytes past the allocated region (into skb_shared_info), which corrupts adjacent heap memory and leads to a kernel panic.

Leer descripción completaMostrar menos

Add a shared helper ioam6_trace_compute_nodelen() in ioam6.c to derive the expected nodelen from the type field, and use it:

Per RFC 9197, bits 12-21 are each short (4-octet) fields, so they are included in IOAM6_MASK_SHORT_FIELDS (changed from 0xff100000 to 0xff1ffc00).

Detalles técnicos trazas, registros y código del informe original

  - in ioam6_iptunnel.c (send path, existing validation) to replace
    the open-coded computation;
  - in exthdrs.c (receive path, ipv6_hop_ioam) to drop packets whose
    nodelen is inconsistent with the type field, before any data is
    written.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 9.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.86%
Percentil entre todas las CVEs puntuadas: 57
Fecha de la puntuación: 6/10/2026

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).

🎯 Técnicas ATT&CK

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

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access95 %
Impacto secundarioT1499.004 Application or System Exploitationimpact85 %

Vulnerabilidad crítica en kernel Linux (AV:N/AC:L/PR:N) explotable remotamente con paquete IPv6 IOAM malformado. Overflow de heap corrompe memoria adyacente causando pánico del kernel (DoS) y potencial ejecución de código arbitrario.

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 Traffic Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Application Isolation and Sandboxing

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-787

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2026-43186",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 9.8,
          "attackVector": "NETWORK",
          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "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": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0",
              "lessThan": "f4d9d4b8fd839719d564651671e24c62c545c23b",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0",
              "lessThan": "fb3c662fafebc5b9d74417ed1de8759f6bb72143",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0",
              "lessThan": "632d233cf2e64a46865ae2c064ae3c9df7c8864f",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0",
              "lessThan": "0591d6509c2ff13f09ea2998434aba0c0472e978",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0",
              "lessThan": "e90346a2f1e8917d5760a44a1f61c44e3b36d96b",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0",
              "lessThan": "ea3632aefc04205436868541638e26f4a74d5637",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0",
              "lessThan": "6db8b56eed62baacaf37486e83378a72635c04cc",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "include/net/ioam6.h",
            "net/ipv6/exthdrs.c",
            "net/ipv6/ioam6.c",
            "net/ipv6/ioam6_iptunnel.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.15"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "5.15",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.15.202",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.165",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.128",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.12.75",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.16",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "6.19.6",
              "versionType": "semver",
              "lessThanOrEqual": "6.19.*"
            },
            {
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "include/net/ioam6.h",
            "net/ipv6/exthdrs.c",
            "net/ipv6/ioam6.c",
            "net/ipv6/ioam6_iptunnel.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-05-06T12:16:37.300",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0591d6509c2ff13f09ea2998434aba0c0472e978",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/632d233cf2e64a46865ae2c064ae3c9df7c8864f",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6db8b56eed62baacaf37486e83378a72635c04cc",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e90346a2f1e8917d5760a44a1f61c44e3b36d96b",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ea3632aefc04205436868541638e26f4a74d5637",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f4d9d4b8fd839719d564651671e24c62c545c23b",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/fb3c662fafebc5b9d74417ed1de8759f6bb72143",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data()\n\nOn the receive path, __ioam6_fill_trace_data() uses trace->nodelen\nto decide how much data to write for each node. It trusts this field\nas-is from the incoming packet, with no consistency check against\ntrace->type (the 24-bit field that tells which data items are\npresent). A crafted packet can set nodelen=0 while setting type bits\n0-21, causing the function to write ~100 bytes past the allocated\nregion (into skb_shared_info), which corrupts adjacent heap memory\nand leads to a kernel panic.\n\nAdd a shared helper ioam6_trace_compute_nodelen() in ioam6.c to\nderive the expected nodelen from the type field, and use it:\n\n  - in ioam6_iptunnel.c (send path, existing validation) to replace\n    the open-coded computation;\n  - in exthdrs.c (receive path, ipv6_hop_ioam) to drop packets whose\n    nodelen is inconsistent with the type field, before any data is\n    written.\n\nPer RFC 9197, bits 12-21 are each short (4-octet) fields, so they\nare included in IOAM6_MASK_SHORT_FIELDS (changed from 0xff100000 to\n0xff1ffc00)."
    }
  ],
  "lastModified": "2026-06-17T10:49:06.890",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "B0330CE4-09CE-43EF-A9C8-CD49FFD1DC98",
              "versionEndExcluding": "5.15.202",
              "versionStartIncluding": "5.15"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "797C7F46-D0BE-4FB8-A502-C5EF8E6B6654",
              "versionEndExcluding": "6.1.165",
              "versionStartIncluding": "5.16"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "851E9353-6C09-4CC9-877E-E09DB164A3C2",
              "versionEndExcluding": "6.6.128",
              "versionStartIncluding": "6.2"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "BCE16369-98ED-41CF-8995-DFDC10B288D2",
              "versionEndExcluding": "6.12.75",
              "versionStartIncluding": "6.7"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "B4B8CDA9-BADF-4CF5-8B3B-702DE8EEA40B",
              "versionEndExcluding": "6.18.16",
              "versionStartIncluding": "6.13"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "373EEEDA-FAA1-4FB4-B6ED-DB4DD99DBE67",
              "versionEndExcluding": "6.19.6",
              "versionStartIncluding": "6.19"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}