« Volver al listado

CVE-2022-49171

Estado: AnalizadaMedia (5.5)—

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

ext4: don't BUG if someone dirty pages without asking ext4 first

[un]pin_user_pages_remote is dirtying pages without properly warning the file system in advance. A related race was noted by Jan Kara in 2018[1]; however, more recently instead of it being a very hard-to-hit race, it could be reliably triggered by process_vm_writev(2) which was discovered by Syzbot[2].

This is technically a bug in mm/gup.c, but arguably ext4 is fragile in that if some other kernel subsystem dirty pages without properly notifying the file system using page_mkwrite(), ext4 will BUG, while other file systems will not BUG (although data will still be lost).

Leer descripción completaMostrar menos

So instead of crashing with a BUG, issue a warning (since there may be potential data loss) and just mark the page as clean to avoid unprivileged denial of service attacks until the problem can be properly fixed. More discussion and background can be found in the thread starting at [2].

[1] https://lore.kernel.org/linux-mm/20180103100430.GE4911@quack2.suse.cz [2] https://lore.kernel.org/r/Yg0m6IjcNmfaSokM@google.com

CVSS

Probabilidad de explotación (EPSS)

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)

Linux — Linux Kernel

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2022-49171",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 5.5,
          "attackVector": "LOCAL",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 3.6,
        "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": "a42afc5f56f319107e987aa6adf2f65d93d527c7",
              "lessThan": "5db60e76edf5680ff1f3a7221036fc44b308f146",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "a42afc5f56f319107e987aa6adf2f65d93d527c7",
              "lessThan": "d666dfaa571465a19f014534a214c255ea33f301",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "a42afc5f56f319107e987aa6adf2f65d93d527c7",
              "lessThan": "0d3a6926f7e8be3c897fa46216ce13b119a9f56a",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "a42afc5f56f319107e987aa6adf2f65d93d527c7",
              "lessThan": "5a016c053f426a73752c3b41b60b497b58694d48",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "a42afc5f56f319107e987aa6adf2f65d93d527c7",
              "lessThan": "330d0e44fc5a47c27df958ecdd4693a3cb1d8b81",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "a42afc5f56f319107e987aa6adf2f65d93d527c7",
              "lessThan": "a0856764dc1276ad2dc7891288c2e9246bf11a37",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "a42afc5f56f319107e987aa6adf2f65d93d527c7",
              "lessThan": "343117559ef41e992e326f7a92da1a8f254dfa8c",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "a42afc5f56f319107e987aa6adf2f65d93d527c7",
              "lessThan": "677c9d30e8487bee6c8e3b034070319d98f6e203",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "a42afc5f56f319107e987aa6adf2f65d93d527c7",
              "lessThan": "cc5095747edfb054ca2068d01af20be3fcc3634f",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "fs/ext4/inode.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.37"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "2.6.37",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "4.9.311",
              "versionType": "semver",
              "lessThanOrEqual": "4.9.*"
            },
            {
              "status": "unaffected",
              "version": "4.14.276",
              "versionType": "semver",
              "lessThanOrEqual": "4.14.*"
            },
            {
              "status": "unaffected",
              "version": "4.19.238",
              "versionType": "semver",
              "lessThanOrEqual": "4.19.*"
            },
            {
              "status": "unaffected",
              "version": "5.4.189",
              "versionType": "semver",
              "lessThanOrEqual": "5.4.*"
            },
            {
              "status": "unaffected",
              "version": "5.10.110",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.33",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "5.16.19",
              "versionType": "semver",
              "lessThanOrEqual": "5.16.*"
            },
            {
              "status": "unaffected",
              "version": "5.17.2",
              "versionType": "semver",
              "lessThanOrEqual": "5.17.*"
            },
            {
              "status": "unaffected",
              "version": "5.18",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "fs/ext4/inode.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2025-02-26T07:00:54.213",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0d3a6926f7e8be3c897fa46216ce13b119a9f56a",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/330d0e44fc5a47c27df958ecdd4693a3cb1d8b81",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/343117559ef41e992e326f7a92da1a8f254dfa8c",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5a016c053f426a73752c3b41b60b497b58694d48",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5db60e76edf5680ff1f3a7221036fc44b308f146",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/677c9d30e8487bee6c8e3b034070319d98f6e203",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a0856764dc1276ad2dc7891288c2e9246bf11a37",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cc5095747edfb054ca2068d01af20be3fcc3634f",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d666dfaa571465a19f014534a214c255ea33f301",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-617"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: don't BUG if someone dirty pages without asking ext4 first\n\n[un]pin_user_pages_remote is dirtying pages without properly warning\nthe file system in advance.  A related race was noted by Jan Kara in\n2018[1]; however, more recently instead of it being a very hard-to-hit\nrace, it could be reliably triggered by process_vm_writev(2) which was\ndiscovered by Syzbot[2].\n\nThis is technically a bug in mm/gup.c, but arguably ext4 is fragile in\nthat if some other kernel subsystem dirty pages without properly\nnotifying the file system using page_mkwrite(), ext4 will BUG, while\nother file systems will not BUG (although data will still be lost).\n\nSo instead of crashing with a BUG, issue a warning (since there may be\npotential data loss) and just mark the page as clean to avoid\nunprivileged denial of service attacks until the problem can be\nproperly fixed.  More discussion and background can be found in the\nthread starting at [2].\n\n[1] https://lore.kernel.org/linux-mm/20180103100430.GE4911@quack2.suse.cz\n[2] https://lore.kernel.org/r/Yg0m6IjcNmfaSokM@google.com"
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: no generar ERRORES si alguien ensucia páginas sin preguntar primero a ext4 [un]pin_user_pages_remote está ensuciando páginas sin advertir adecuadamente al sistema de archivos con anticipación. Jan Kara notó una ejecución relacionada en 2018[1]; sin embargo, más recientemente, en lugar de ser una ejecución muy difícil de alcanzar, podría ser activada de manera confiable por process_vm_writev(2) que fue descubierto por Syzbot[2]. Técnicamente, esto es un error en mm/gup.c, pero podría decirse que ext4 es frágil en el sentido de que si algún otro subsistema del kernel ensucia páginas sin notificar adecuadamente al sistema de archivos usando page_mkwrite(), ext4 generará ERRORES, mientras que otros sistemas de archivos no generarán ERRORES (aunque aún se perderán datos). Entonces, en lugar de bloquearse con un ERROR, emita una advertencia (ya que puede haber una posible pérdida de datos) y simplemente marque la página como limpia para evitar ataques de denegación de servicio sin privilegios hasta que el problema pueda solucionarse correctamente. Se puede encontrar más discusión y antecedentes en el hilo que comienza en [2]. [1] https://lore.kernel.org/linux-mm/20180103100430.GE4911@quack2.suse.cz [2] https://lore.kernel.org/r/Yg0m6IjcNmfaSokM@google.com"
    }
  ],
  "lastModified": "2026-06-17T05:17:16.323",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "C86EFD13-93D4-4385-83E8-C665BE8F570F",
              "versionEndExcluding": "4.9.311"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "6D9B028C-6313-47F9-94B7-5F8122345E49",
              "versionEndExcluding": "4.14.276",
              "versionStartIncluding": "4.10"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "FA28527A-11D3-41D2-9C4C-ECAC0D6A4A2D",
              "versionEndExcluding": "4.19.238",
              "versionStartIncluding": "4.15"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "8CB6E8F5-C2B1-46F3-A807-0F6104AC340F",
              "versionEndExcluding": "5.4.189",
              "versionStartIncluding": "4.20"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "91D3BFD0-D3F3-4018-957C-96CCBF357D79",
              "versionEndExcluding": "5.10.110",
              "versionStartIncluding": "5.5"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "27C42AE8-B387-43E2-938A-E1C8B40BE6D5",
              "versionEndExcluding": "5.15.33",
              "versionStartIncluding": "5.11"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "20C43679-0439-405A-B97F-685BEE50613B",
              "versionEndExcluding": "5.16.19",
              "versionStartIncluding": "5.16"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "210C679C-CF84-44A3-8939-E629C87E54BF",
              "versionEndExcluding": "5.17.2",
              "versionStartIncluding": "5.17"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}