« Volver al listado

CVE-2026-31578

Estado: ModificadaAlta (7.8)—

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

media: as102: fix to not free memory after the device is registered in as102_usb_probe()

In as102_usb driver, the following race condition occurs: ``` CPU0 CPU1 as102_usb_probe() kzalloc(); // alloc as102_dev_t .... usb_register_dev(); fd = sys_open("/path/to/dev"); // open as102 fd .... usb_deregister_dev(); .... kfree(); // free as102_dev_t .... sys_close(fd); as102_release() // UAF!! as102_usb_release() kfree(); // DFB!! ```

When a USB character device registered with usb_register_dev() is later unregistered (via usb_deregister_dev() or disconnect), the device node is removed so new open() calls fail.

Leer descripción completaMostrar menos

However, file descriptors that are already open do not go away immediately: they remain valid until the last reference is dropped and the driver's .release() is invoked.

In as102, as102_usb_probe() calls usb_register_dev() and then, on an error path, does usb_deregister_dev() and frees as102_dev_t right away. If userspace raced a successful open() before the deregistration, that open FD will later hit as102_release() --> as102_usb_release() and access or free as102_dev_t again, occur a race to use-after-free and double-free vuln.

The fix is to never kfree(as102_dev_t) directly once usb_register_dev() has succeeded. After deregistration, defer freeing memory to .release().

In other words, let release() perform the last kfree when the final open FD is closed.

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).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

Vulnerabilidad de use-after-free (CWE-416) en driver USB Linux con acceso local (AV:L) sin interacción (UI:N), alcanzable con privilegios de usuario (PR:L). Permite ejecutar código arbitrario al acceder a memoria liberada.

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

Tecnologías afectadas (1)

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-31578",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "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": "cd19f7d3e39b3160595d56bb3e3a2bf4f7f4669c",
              "lessThan": "0d36653a3a821e5a974798adb347b3ea09332914",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "cd19f7d3e39b3160595d56bb3e3a2bf4f7f4669c",
              "lessThan": "25d500cf391e384356a612b85cf60b353ad3cd0c",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "cd19f7d3e39b3160595d56bb3e3a2bf4f7f4669c",
              "lessThan": "07ceb444c8f627cf863864d4274b5a77769725ed",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "cd19f7d3e39b3160595d56bb3e3a2bf4f7f4669c",
              "lessThan": "cb8092038e95dc1113a68e63762de40fff61ba71",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "cd19f7d3e39b3160595d56bb3e3a2bf4f7f4669c",
              "lessThan": "582fbecb3756330006fe1950762412a68c2cacd2",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "cd19f7d3e39b3160595d56bb3e3a2bf4f7f4669c",
              "lessThan": "09e9206008b887aa553733bd915d73131071a086",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "cd19f7d3e39b3160595d56bb3e3a2bf4f7f4669c",
              "lessThan": "2eeae47a438694408189138048a786be99954032",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "cd19f7d3e39b3160595d56bb3e3a2bf4f7f4669c",
              "lessThan": "7e5aedf6059cba2a669d86caeaf5a51f33ec85a1",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "cd19f7d3e39b3160595d56bb3e3a2bf4f7f4669c",
              "lessThan": "8bd29dbe03fc5b0f039ab2395ff37b64236d2f0c",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "drivers/media/usb/as102/as102_usb_drv.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.14"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "3.14",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.10.258",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.209",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.175",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.136",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.12.83",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.24",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "6.19.14",
              "versionType": "semver",
              "lessThanOrEqual": "6.19.*"
            },
            {
              "status": "unaffected",
              "version": "7.0.1",
              "versionType": "semver",
              "lessThanOrEqual": "7.0.*"
            },
            {
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "drivers/media/usb/as102/as102_usb_drv.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-04-24T15:16:32.480",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/07ceb444c8f627cf863864d4274b5a77769725ed",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/09e9206008b887aa553733bd915d73131071a086",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/0d36653a3a821e5a974798adb347b3ea09332914",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/25d500cf391e384356a612b85cf60b353ad3cd0c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2eeae47a438694408189138048a786be99954032",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/582fbecb3756330006fe1950762412a68c2cacd2",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7e5aedf6059cba2a669d86caeaf5a51f33ec85a1",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8bd29dbe03fc5b0f039ab2395ff37b64236d2f0c",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cb8092038e95dc1113a68e63762de40fff61ba71",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: as102: fix to not free memory after the device is registered in as102_usb_probe()\n\nIn as102_usb driver, the following race condition occurs:\n```\n\t\tCPU0\t\t\t\t\t\tCPU1\nas102_usb_probe()\n  kzalloc(); // alloc as102_dev_t\n  ....\n  usb_register_dev();\n\t\t\t\t\t\tfd = sys_open(\"/path/to/dev\"); // open as102 fd\n\t\t\t\t\t\t....\n  usb_deregister_dev();\n  ....\n  kfree(); // free as102_dev_t\n  ....\n\t\t\t\t\t\tsys_close(fd);\n\t\t\t\t\t\t  as102_release() // UAF!!\n\t\t\t\t\t\t    as102_usb_release()\n\t\t\t\t\t\t      kfree(); // DFB!!\n```\n\nWhen a USB character device registered with usb_register_dev() is later\nunregistered (via usb_deregister_dev() or disconnect), the device node is\nremoved so new open() calls fail. However, file descriptors that are\nalready open do not go away immediately: they remain valid until the last\nreference is dropped and the driver's .release() is invoked.\n\nIn as102, as102_usb_probe() calls usb_register_dev() and then, on an\nerror path, does usb_deregister_dev() and frees as102_dev_t right away.\nIf userspace raced a successful open() before the deregistration, that\nopen FD will later hit as102_release() --> as102_usb_release() and access\nor free as102_dev_t again, occur a race to use-after-free and\ndouble-free vuln.\n\nThe fix is to never kfree(as102_dev_t) directly once usb_register_dev()\nhas succeeded. After deregistration, defer freeing memory to .release().\n\nIn other words, let release() perform the last kfree when the final open\nFD is closed."
    }
  ],
  "lastModified": "2026-06-17T10:34:00.887",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "14109CEF-714B-4029-A318-97AA58A01833",
              "versionEndExcluding": "6.6.136"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7F0AE5B5-23AC-4DCC-B37A-51CA1DAE7BA8",
              "versionEndExcluding": "6.12.83",
              "versionStartIncluding": "6.7"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "8126B8B8-6D0B-4443-86C1-672AEE893555",
              "versionEndExcluding": "6.18.24",
              "versionStartIncluding": "6.13"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "D6A8A074-BBF4-4803-ABED-519A839435BB",
              "versionEndExcluding": "6.19.14",
              "versionStartIncluding": "6.19"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "9B5888AB-7403-4335-89E4-21CC0B48366A",
              "versionEndExcluding": "7.0.1",
              "versionStartIncluding": "7.0"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}