CVE-2026-64322

Estado: AnalizadaAlta (7.8)—

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

udf: validate sparing table length as an entry count, not a byte count

udf_load_sparable_map() accepts a sparing table when

is false, i.e. it treats reallocationTableLen as a number of BYTES that must fit in the block. But the table is walked as an array of 8-byte sparingEntry elements:

in udf_get_pblock_spar15() and udf_relocate_blocks(). A reallocationTableLen of N therefore passes the check whenever sizeof(*st) + N <= blocksize, yet the consumers index sizeof(*st) + N * sizeof(struct sparingEntry) bytes -- up to ~8x the block. On a crafted UDF image this is an out-of-bounds read in udf_get_pblock_spar15(); udf_relocate_blocks() additionally feeds the same length to udf_update_tag(), whose crc_itu_t() reads far past the block, and its memmove() through st->mapEntry[] is an out-of-bounds write.

Leer descripción completaMostrar menos

Validate reallocationTableLen as the entry count it is, with struct_size().

Detalles técnicos trazas, registros y código del informe original

	sizeof(*st) + le16_to_cpu(st->reallocationTableLen) > sb->s_blocksize

	for (i = 0; i < le16_to_cpu(st->reallocationTableLen); i++) {
		struct sparingEntry *entry = &st->mapEntry[i];
		... entry->origLocation ...
	}

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 7.8

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: 5/10/2026

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.

ExplotaciónT1068 Exploitation for Privilege Escalationprivilege escalation85 %
Impacto principalT1005 Data from Local Systemcollection80 %
Impacto secundarioT1565.001 Stored Data Manipulationimpact75 %

Vulnerabilidad local (AV:L, PR:L) que permite lectura y escritura fuera de límites en tabla UDF al fallar validación de longitud; escalada mediante corrupción de memoria en 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

Threat Intelligence Program Restrict File and Directory Permissions Remote Data Storage Execution Prevention Encrypt Sensitive Information Application Isolation and Sandboxing

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-787

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2026-64322",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.8,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 1.8
      }
    ]
  },
  "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": "1df2ae31c724e57be9d7ac00d78db8a5dabdd050",
              "lessThan": "eeb0f3e193f8e523d03e4c9e084f6b4875f50e8e",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1df2ae31c724e57be9d7ac00d78db8a5dabdd050",
              "lessThan": "0a9b79a951cfd70a9d31ca01ae2d08a20bb730e9",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1df2ae31c724e57be9d7ac00d78db8a5dabdd050",
              "lessThan": "2d726135099313958f8975532a2e15322ff150ce",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1df2ae31c724e57be9d7ac00d78db8a5dabdd050",
              "lessThan": "7285276aa50d2839afb5957ffd491ad282dc8f72",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1df2ae31c724e57be9d7ac00d78db8a5dabdd050",
              "lessThan": "2a219acb2ce674d99bbd1b7b35ed8c384dac7200",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1df2ae31c724e57be9d7ac00d78db8a5dabdd050",
              "lessThan": "04f4599a9efb90992d072a814960edf0cd62805d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1df2ae31c724e57be9d7ac00d78db8a5dabdd050",
              "lessThan": "7f7774b9da0ef17b87bfa238cf966ad0b3376150",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1df2ae31c724e57be9d7ac00d78db8a5dabdd050",
              "lessThan": "3ec997bd5508e9b25210b5bbec89031629cdb093",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e240873cb4a9fd18de60a817100a96fe670d4359",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9ae30e324a96d0328a575329d7a95a09b3318601",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b1c5701ad6b3e5d21d16f65475651cfaaa41e7aa",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "a9f1af04f086656246f30354fb4564ce3b08c4a0",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "4836ee563d65bb492f907cbe267a5761b9693e4d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "2.6.32.60",
              "lessThan": "2.6.33",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "2.6.34.14",
              "lessThan": "2.6.35",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "3.0.37",
              "lessThan": "3.1",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "3.2.23",
              "lessThan": "3.3",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "3.4.5",
              "lessThan": "3.5",
              "versionType": "semver"
            }
          ],
          "programFiles": [
            "fs/udf/super.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.5"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "3.5",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.10.261",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.212",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.12.96",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.39",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.1.4",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "fs/udf/super.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-07-25T10:17:13.640",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/04f4599a9efb90992d072a814960edf0cd62805d",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/0a9b79a951cfd70a9d31ca01ae2d08a20bb730e9",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2a219acb2ce674d99bbd1b7b35ed8c384dac7200",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2d726135099313958f8975532a2e15322ff150ce",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/3ec997bd5508e9b25210b5bbec89031629cdb093",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7285276aa50d2839afb5957ffd491ad282dc8f72",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7f7774b9da0ef17b87bfa238cf966ad0b3376150",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/eeb0f3e193f8e523d03e4c9e084f6b4875f50e8e",
      "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\nudf: validate sparing table length as an entry count, not a byte count\n\nudf_load_sparable_map() accepts a sparing table when\n\n\tsizeof(*st) + le16_to_cpu(st->reallocationTableLen) > sb->s_blocksize\n\nis false, i.e. it treats reallocationTableLen as a number of BYTES that\nmust fit in the block.  But the table is walked as an array of 8-byte\nsparingEntry elements:\n\n\tfor (i = 0; i < le16_to_cpu(st->reallocationTableLen); i++) {\n\t\tstruct sparingEntry *entry = &st->mapEntry[i];\n\t\t... entry->origLocation ...\n\t}\n\nin udf_get_pblock_spar15() and udf_relocate_blocks().  A\nreallocationTableLen of N therefore passes the check whenever\nsizeof(*st) + N <= blocksize, yet the consumers index\nsizeof(*st) + N * sizeof(struct sparingEntry) bytes -- up to ~8x the\nblock.  On a crafted UDF image this is an out-of-bounds read in\nudf_get_pblock_spar15(); udf_relocate_blocks() additionally feeds the\nsame length to udf_update_tag(), whose crc_itu_t() reads far past the\nblock, and its memmove() through st->mapEntry[] is an out-of-bounds\nwrite.\n\nValidate reallocationTableLen as the entry count it is, with\nstruct_size()."
    }
  ],
  "lastModified": "2026-09-04T14:52:46.270",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "571B40BF-08B7-41AC-806B-0E35A53D328E",
              "versionEndExcluding": "2.6.33",
              "versionStartIncluding": "2.6.32.60"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "C1AC9B20-1038-4F47-A063-9EE430E432F3",
              "versionEndExcluding": "2.6.35",
              "versionStartIncluding": "2.6.34.14"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "75F31EC0-3D1C-48F0-A8B9-0B5A519046DD",
              "versionEndExcluding": "3.1",
              "versionStartIncluding": "3.0.37"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "FC48A9C2-AC26-44CD-B13A-F46DF05DDD3C",
              "versionEndExcluding": "3.3",
              "versionStartIncluding": "3.2.23"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "12003DF5-A23E-4886-9953-702081F7FC56",
              "versionEndExcluding": "3.5",
              "versionStartIncluding": "3.4.5"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "3300EEBE-67F9-4024-8019-0ACE4F414608",
              "versionEndExcluding": "5.10.261",
              "versionStartIncluding": "3.5.1"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "8E99FB01-CD93-41AF-A653-3F450652B9A6",
              "versionEndExcluding": "5.15.212",
              "versionStartIncluding": "5.11"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "092233C7-F4E0-40C8-BD4D-A28FE50DFE20",
              "versionEndExcluding": "6.1.178",
              "versionStartIncluding": "5.16"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7046B092-F810-4440-ACE6-60218518EECE",
              "versionEndExcluding": "6.6.145",
              "versionStartIncluding": "6.2"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "38A8100E-2B1A-462F-AEE9-8901B870FEF2",
              "versionEndExcluding": "6.12.96",
              "versionStartIncluding": "6.7"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "914AE4BC-3D59-4C5A-9DB5-9CE327B429F7",
              "versionEndExcluding": "6.18.39",
              "versionStartIncluding": "6.13"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42",
              "versionEndExcluding": "7.1.4",
              "versionStartIncluding": "6.19"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:3.5:-:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "71555F5B-DEB2-417A-8E33-90276DD2EFB8"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:3.5:rc5:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7F0CC423-9BE8-4B1C-8179-E3E24693BEAA"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:3.5:rc6:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F9893E78-1974-4ED0-B4DB-CD2F9161E61A"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:3.5:rc7:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "1E1655C7-B886-47A0-AF2B-B54A25AA91FF"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}