CVE-2026-74403

Estado: RecibidaAlta (7.8)—

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

crypto: ccp - Check for page allocation failure correctly in TIO

Sashiko notes:

> if __snp_alloc_firmware_pages() returns NULL under memory pressure, is it > safe to pass it directly to page_address()? > > On architectures without HASHED_PAGE_VIRTUAL, page_address(NULL) might > compute a deterministic but invalid, non-zero virtual address. The > subsequent if (tio_status) check would then evaluate to true, and > sev_tsm_init_locked() would dereference the invalid pointer.

Indeed, page_address(NULL) will return non-NULL garbage here. Fix this by checking the page allocation itself for NULL, not the resulting virtual address.

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: 5
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 principalT1059 Command and Scripting Interpreterexecution75 %

Vulnerabilidad de escalada local en kernel Linux (AV:L, PR:L) que permite ejecución de código mediante desreferencia de puntero nulo sin autenticación adicional.

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

Execution Prevention Threat Intelligence Program Restrict Web-Based Content Privileged Account Management Limit Software Installation Behavior Prevention on Endpoint

Tecnologías afectadas (1)

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

Linux — Linux Kernel^AI

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2026-74403",
  "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": "4be423572da1f4c11f45168e3fafda870ddac9f8",
              "lessThan": "17e1aae19a06d9f6da4b46d54fa2aeab77ec0c69",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "4be423572da1f4c11f45168e3fafda870ddac9f8",
              "lessThan": "a8d5370eef00eca132a292b1901c9914c817e385",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "drivers/crypto/ccp/sev-dev.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.19"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "6.19",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "drivers/crypto/ccp/sev-dev.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-08-15T06:22:42.340",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/17e1aae19a06d9f6da4b46d54fa2aeab77ec0c69",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a8d5370eef00eca132a292b1901c9914c817e385",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: ccp - Check for page allocation failure correctly in TIO\n\nSashiko notes:\n\n> if __snp_alloc_firmware_pages() returns NULL under memory pressure, is it\n> safe to pass it directly to page_address()?\n>\n> On architectures without HASHED_PAGE_VIRTUAL, page_address(NULL) might\n> compute a deterministic but invalid, non-zero virtual address. The\n> subsequent if (tio_status) check would then evaluate to true, and\n> sev_tsm_init_locked() would dereference the invalid pointer.\n\nIndeed, page_address(NULL) will return non-NULL garbage here. Fix this by\nchecking the page allocation itself for NULL, not the resulting virtual\naddress."
    }
  ],
  "lastModified": "2026-08-17T06:19:35.503",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}