CVE-2026-74600

{
  "id": "CVE-2026-74600",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-22T16:16:32.430",
  "lastModified": "2026-10-30T13:20:03.103",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/page_table_check: skip special zero mappings\n\npage_table_check_set() and page_table_check_clear() account mappings based\non PageAnon().  Shared zero-page PTEs and huge zero PMDs are special\nmappings, but page_table_check can still account them as file-backed\npages.\n\nAn unprivileged process can populate enough zero mappings to overflow\nfile_map_count and hit the existing BUG_ON().  The PTE path can do this\nwith the shared zero page, and the PMD path can do the same with huge zero\nmappings.\n\nSkip special zero mappings in the user page-table accounting paths.  Keep\nthe PTE-side pte_special() check, and identify huge zero PMDs from the\nmapped folio instead of pmd_special().  That covers architectures where\npmd_special() is a no-op without adding huge_zero_pfn checks to the\ngeneric counter helpers."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nmm/page_table_check: omitir mapeos especiales de cero\n\npage_table_check_set() y page_table_check_clear() contabilizan los mapeos basándose en PageAnon(). Los PTEs de página cero compartida y los PMDs de cero enormes son mapeos especiales, pero page_table_check aún puede contabilizarlos como páginas respaldadas por archivos.\n\nUn proceso sin privilegios puede poblar suficientes mapeos de cero para desbordar file_map_count y activar el BUG_ON() existente. La ruta PTE puede hacer esto con la página cero compartida, y la ruta PMD puede hacer lo mismo con mapeos de cero enormes.\n\nOmitir los mapeos especiales de cero en las rutas de contabilidad de la tabla de páginas de usuario. Mantener la verificación pte_special() del lado PTE, e identificar los PMDs de cero enormes desde el folio mapeado en lugar de pmd_special(). Eso cubre arquitecturas donde pmd_special() es una no-op sin añadir verificaciones de huge_zero_pfn a los ayudantes de contador genéricos."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "mm/page_table_check.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "df4e817b710809425d899340dbfa8504a3ca4ba5",
              "lessThan": "084b031a1cc13b1d50b9660baace0b7eba52bebe",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "df4e817b710809425d899340dbfa8504a3ca4ba5",
              "lessThan": "f6cf9832e677ec07b1675782bd2bad472cfd3cdc",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "df4e817b710809425d899340dbfa8504a3ca4ba5",
              "lessThan": "51e16e5adadaa78b56f31a1cb02eb7267787625e",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "df4e817b710809425d899340dbfa8504a3ca4ba5",
              "lessThan": "7755be923e325dc300f4b0c3e1ad7e91b28b3cb9",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "df4e817b710809425d899340dbfa8504a3ca4ba5",
              "lessThan": "b726eb3c94d23e09da0e0f46b0fa09fb2b5d99cc",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "df4e817b710809425d899340dbfa8504a3ca4ba5",
              "lessThan": "8db4bab826ccc9ec10fa41736a48031cd338d392",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "mm/page_table_check.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.17",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.17",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.114",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.46",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.9",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/084b031a1cc13b1d50b9660baace0b7eba52bebe",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/51e16e5adadaa78b56f31a1cb02eb7267787625e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7755be923e325dc300f4b0c3e1ad7e91b28b3cb9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8db4bab826ccc9ec10fa41736a48031cd338d392",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b726eb3c94d23e09da0e0f46b0fa09fb2b5d99cc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f6cf9832e677ec07b1675782bd2bad472cfd3cdc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}