CVE-2026-74359

Estado: RecibidaAlta (7.8)—

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

configfs_lookup(): don't leave ->s_dentry dangling on failure

Normally ->s_dentry is cleared when dentry it's pointing to becomes negative (on eviction, realistically). However, that only happens if dentry gets to be positive in the first place; in case of inode allocation failure dentry never becomes positive, so ->d_iput() is not called at all.

We do part of what normally would've been done by configfs_d_iput() (dropping the reference to configfs_dirent) manually, but we do not clear ->s_dentry there. Sloppy as it is, it does not matter in case of configfs_create_{dir,link}() - there configfs_dirent does not survive dropping the sole reference to it.

Leer descripción completaMostrar menos

However, for configfs_lookup() it *does* survive, with a dangling pointer to soon to be freed dentry sitting it its ->s_dentry.

Subsequent getdents(2) in that directory will end up dereferencing that pointer in order to pick the inode number. Use after free...

This is the minimal fix; the right approach is to set the linkage between dentry and configfs_dirent only after we know that we have an inode, but that takes more surgery and the bug had been there since 2006, so...

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 principalT1499.004 Application or System Exploitationimpact75 %
Impacto secundarioT1005 Data from Local Systemcollection60 %

Vulnerabilidad local con PR:L que permite escalar privilegios vía use-after-free en configfs_lookup(). El defecto causa dereferencia de puntero dangling en getdents(2), permitiendo DoS o lectura de memoria del 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 Filter Network Traffic Execution Prevention Application Isolation and Sandboxing Exploit Protection Update Software

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-2026-74359",
  "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": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "lessThan": "3e83b2203aa59bd279e4f677ec793d49dc9d019e",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "lessThan": "b6e9c82522ddaa3ac0706b295ff4a71975d4f883",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "lessThan": "eee07d769da5ac4e4f7bd0bc17828646a318d499",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "lessThan": "9c747dcee164ead300de90550ad9e4122f0d1bbb",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "lessThan": "c3b073a209a9baa691b744318ac929fecdd8847c",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "lessThan": "57088b06109f3222963c639d8d743f42c2899b13",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "lessThan": "10da12d352b7b2bb330a8609fdda9a58bf0e9856",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "fs/configfs/dir.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.16"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "2.6.16",
              "versionType": "semver"
            },
            {
              "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": "6.12.97",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "fs/configfs/dir.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-08-15T06:22:37.430",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/10da12d352b7b2bb330a8609fdda9a58bf0e9856",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/3e83b2203aa59bd279e4f677ec793d49dc9d019e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/57088b06109f3222963c639d8d743f42c2899b13",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9c747dcee164ead300de90550ad9e4122f0d1bbb",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b6e9c82522ddaa3ac0706b295ff4a71975d4f883",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c3b073a209a9baa691b744318ac929fecdd8847c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/eee07d769da5ac4e4f7bd0bc17828646a318d499",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nconfigfs_lookup(): don't leave ->s_dentry dangling on failure\n\nNormally ->s_dentry is cleared when dentry it's pointing to becomes\nnegative (on eviction, realistically).  However, that only happens\nif dentry gets to be positive in the first place; in case of inode\nallocation failure dentry never becomes positive, so ->d_iput()\nis not called at all.\n\nWe do part of what normally would've been done by configfs_d_iput()\n(dropping the reference to configfs_dirent) manually, but we do\nnot clear ->s_dentry there.  Sloppy as it is, it does not matter in\ncase of configfs_create_{dir,link}() - there configfs_dirent does\nnot survive dropping the sole reference to it.\n\nHowever, for configfs_lookup() it *does* survive, with a dangling\npointer to soon to be freed dentry sitting it its ->s_dentry.\n\nSubsequent getdents(2) in that directory will end up dereferencing\nthat pointer in order to pick the inode number.  Use after free...\n\nThis is the minimal fix; the right approach is to set the linkage\nbetween dentry and configfs_dirent only after we know that we have\nan inode, but that takes more surgery and the bug had been there\nsince 2006, so..."
    }
  ],
  "lastModified": "2026-08-17T06:19:30.627",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}