CVE-2026-53193

Estado: AnalizadaAlta (7.8)—

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

ALSA: timer: Forcibly close timer instances at closing

When snd_timer object is freed via snd_timer_free() and still pending snd_timer_instance objects are assigned to the timer object, it tries to unlink all instances and just set NULL to each ti->timer, then releases the resources immediately.

Leer descripción completaMostrar menos

The problem is, however, when there are slave timer instances that are associated with a master instance linked to this timer: namely, those slave instances still point to the freed timer object although the master instance is unlinked, which may lead to user-after-free. The bug can be easily triggered particularly when a new userspace-driven timers (CONFIG_SND_UTIMER) is involved, since it can create and delete the timer object via a simple file open/close, while the other applications may keep accessing to that timer.

This patch is an attempt to paper over the problem above: now instead of just unlinking, call snd_timer_close[_locked]() forcibly for each pending timer instance, so that all assigned slave timer instances are properly detached, too. Since snd_timer_close() might be called later by the driver that created that instance, the check of SNDRV_TIMER_IFLG_DEAD is added at the beginning, too.

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: 0.14%
Percentil entre todas las CVEs puntuadas: 3
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 escalation75 %
Impacto principalT1059 Command and Scripting Interpreterexecution60 %

CWE-416 (use-after-free) en kernel Linux con acceso local (AV:L, PR:L) permite ejecutar código arbitrario con privilegios elevados tras liberar memoria en objetos de timer ALSA.

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)

Linux — Linux Kernel

CWE

CWE-416

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2026-53193",
  "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": "37745918e0e7575bc40f38da93a99b9fa6406224",
              "lessThan": "586b219a22b1032b28b8bd356b963276c5e5bf53",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "37745918e0e7575bc40f38da93a99b9fa6406224",
              "lessThan": "f46093dd22969037beb1fce2e043f3236be41c92",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "37745918e0e7575bc40f38da93a99b9fa6406224",
              "lessThan": "60e73ab87b84bbd6bd7ddd1d16019a3a3705ab8f",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "37745918e0e7575bc40f38da93a99b9fa6406224",
              "lessThan": "da3039e91d1f835874ed6e9a33ea19ee80c2cb92",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "sound/core/timer.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.12"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "6.12",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "6.12.94",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.36",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.0.13",
              "versionType": "semver",
              "lessThanOrEqual": "7.0.*"
            },
            {
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "sound/core/timer.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-06-25T09:16:36.757",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/586b219a22b1032b28b8bd356b963276c5e5bf53",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/60e73ab87b84bbd6bd7ddd1d16019a3a3705ab8f",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/da3039e91d1f835874ed6e9a33ea19ee80c2cb92",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f46093dd22969037beb1fce2e043f3236be41c92",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Analyzed",
  "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\nALSA: timer: Forcibly close timer instances at closing\n\nWhen snd_timer object is freed via snd_timer_free() and still pending\nsnd_timer_instance objects are assigned to the timer object, it tries\nto unlink all instances and just set NULL to each ti->timer, then\nreleases the resources immediately.  The problem is, however, when\nthere are slave timer instances that are associated with a master\ninstance linked to this timer: namely, those slave instances still\npoint to the freed timer object although the master instance is\nunlinked, which may lead to user-after-free.  The bug can be easily\ntriggered particularly when a new userspace-driven timers\n(CONFIG_SND_UTIMER) is involved, since it can create and delete the\ntimer object via a simple file open/close, while the other\napplications may keep accessing to that timer.\n\nThis patch is an attempt to paper over the problem above: now instead\nof just unlinking, call snd_timer_close[_locked]() forcibly for each\npending timer instance, so that all assigned slave timer instances are\nproperly detached, too.  Since snd_timer_close() might be called later\nby the driver that created that instance, the check of\nSNDRV_TIMER_IFLG_DEAD is added at the beginning, too."
    }
  ],
  "lastModified": "2026-07-06T12:37:04.170",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7327870E-8777-43EF-92CB-081E4B51D6F9",
              "versionEndExcluding": "6.12.94",
              "versionStartIncluding": "6.12"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "389025D2-958D-41BD-BD96-70ED1033A9F3",
              "versionEndExcluding": "6.18.36",
              "versionStartIncluding": "6.13"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "6A64BF9F-3BCA-42FD-98CB-8F03474D2B1E",
              "versionEndExcluding": "7.0.13",
              "versionStartIncluding": "6.19"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "0D38F0BF-A728-4133-A358-D44A2F7EE6D6"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "EC732D08-5F7B-46D9-B154-E60C7F4F0A97"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "E5910A9D-F60A-409A-B486-FE66BFEBA9B9"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "81DFF19E-9CF8-49C6-8C36-1E4038622933"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "B0E8FC71-3952-444C-83E9-718DBBBEC615"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "1039E95A-8CC3-4C88-8FF9-5C08EEB861C9"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}