CVE-2022-49939

Estado: ModificadaAlta (7)—

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

binder: fix UAF of ref->proc caused by race condition

A transaction of type BINDER_TYPE_WEAK_HANDLE can fail to increment the reference for a node. In this case, the target proc normally releases the failed reference upon close as expected. However, if the target is dying in parallel the call will race with binder_deferred_release(), so the target could have released all of its references by now leaving the cleanup of the new failed reference unhandled.

The transaction then ends and the target proc gets released making the ref->proc now a dangling pointer.

Leer descripción completaMostrar menos

Later on, ref->node is closed and we attempt to take spin_lock(&ref->proc->inner_lock), which leads to the use-after-free bug reported below. Let's fix this by cleaning up the failed reference on the spot instead of relying on the target to do so.

Detalles técnicos trazas, registros y código del informe original

  ==================================================================
  BUG: KASAN: use-after-free in _raw_spin_lock+0xa8/0x150
  Write of size 4 at addr ffff5ca207094238 by task kworker/1:0/590

  CPU: 1 PID: 590 Comm: kworker/1:0 Not tainted 5.19.0-rc8 #10
  Hardware name: linux,dummy-virt (DT)
  Workqueue: events binder_deferred_func
  Call trace:
   dump_backtrace.part.0+0x1d0/0x1e0
   show_stack+0x18/0x70
   dump_stack_lvl+0x68/0x84
   print_report+0x2e4/0x61c
   kasan_report+0xa4/0x110
   kasan_check_range+0xfc/0x1a4
   __kasan_check_write+0x3c/0x50
   _raw_spin_lock+0xa8/0x150
   binder_deferred_func+0x5e0/0x9b0
   process_one_work+0x38c/0x5f0
   worker_thread+0x9c/0x694
   kthread+0x188/0x190
   ret_from_fork+0x10/0x20

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 7

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: 6/10/2026

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 secundarioT1059 Command and Scripting Interpreterexecution70 %

Vulnerabilidad local (AV:L, PR:L) de use-after-free en binder kernel que permite escalada de privilegios (elevar a root) o ejecución de código arbitrario mediante race condition en transacciones BINDER_TYPE_WEAK_HANDLE.

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-362, CWE-416

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2022-49939",
  "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
      },
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "HIGH",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 1
      }
    ]
  },
  "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": "372e3147df7016ebeaa372939e8774a1292db558",
              "lessThan": "229f47603dd306bc0eb1a831439adb8e48bb0eae",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "372e3147df7016ebeaa372939e8774a1292db558",
              "lessThan": "06e5b43ca4dab06a92bf4c2f33766e6fb11b880a",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "372e3147df7016ebeaa372939e8774a1292db558",
              "lessThan": "30d0901b307f27d36b2655fb3048cf31ee0e89c0",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "372e3147df7016ebeaa372939e8774a1292db558",
              "lessThan": "9629f2dfdb1dad294b468038ff8e161e94d0b609",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "372e3147df7016ebeaa372939e8774a1292db558",
              "lessThan": "c2a4b5dc8fa71af73bab704d0cac42ac39767ed6",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "372e3147df7016ebeaa372939e8774a1292db558",
              "lessThan": "603a47f2ae56bf68288784d3c0a8c5b8e0a827ed",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "372e3147df7016ebeaa372939e8774a1292db558",
              "lessThan": "a0e44c64b6061dda7e00b7c458e4523e2331b739",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "drivers/android/binder.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.14"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "4.14",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "4.14.293",
              "versionType": "semver",
              "lessThanOrEqual": "4.14.*"
            },
            {
              "status": "unaffected",
              "version": "4.19.258",
              "versionType": "semver",
              "lessThanOrEqual": "4.19.*"
            },
            {
              "status": "unaffected",
              "version": "5.4.213",
              "versionType": "semver",
              "lessThanOrEqual": "5.4.*"
            },
            {
              "status": "unaffected",
              "version": "5.10.142",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.66",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "5.19.8",
              "versionType": "semver",
              "lessThanOrEqual": "5.19.*"
            },
            {
              "status": "unaffected",
              "version": "6.0",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "drivers/android/binder.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2025-06-18T11:15:20.793",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/06e5b43ca4dab06a92bf4c2f33766e6fb11b880a",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/229f47603dd306bc0eb1a831439adb8e48bb0eae",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/30d0901b307f27d36b2655fb3048cf31ee0e89c0",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/603a47f2ae56bf68288784d3c0a8c5b8e0a827ed",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9629f2dfdb1dad294b468038ff8e161e94d0b609",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a0e44c64b6061dda7e00b7c458e4523e2331b739",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c2a4b5dc8fa71af73bab704d0cac42ac39767ed6",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-362"
        },
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbinder: fix UAF of ref->proc caused by race condition\n\nA transaction of type BINDER_TYPE_WEAK_HANDLE can fail to increment the\nreference for a node. In this case, the target proc normally releases\nthe failed reference upon close as expected. However, if the target is\ndying in parallel the call will race with binder_deferred_release(), so\nthe target could have released all of its references by now leaving the\ncleanup of the new failed reference unhandled.\n\nThe transaction then ends and the target proc gets released making the\nref->proc now a dangling pointer. Later on, ref->node is closed and we\nattempt to take spin_lock(&ref->proc->inner_lock), which leads to the\nuse-after-free bug reported below. Let's fix this by cleaning up the\nfailed reference on the spot instead of relying on the target to do so.\n\n  ==================================================================\n  BUG: KASAN: use-after-free in _raw_spin_lock+0xa8/0x150\n  Write of size 4 at addr ffff5ca207094238 by task kworker/1:0/590\n\n  CPU: 1 PID: 590 Comm: kworker/1:0 Not tainted 5.19.0-rc8 #10\n  Hardware name: linux,dummy-virt (DT)\n  Workqueue: events binder_deferred_func\n  Call trace:\n   dump_backtrace.part.0+0x1d0/0x1e0\n   show_stack+0x18/0x70\n   dump_stack_lvl+0x68/0x84\n   print_report+0x2e4/0x61c\n   kasan_report+0xa4/0x110\n   kasan_check_range+0xfc/0x1a4\n   __kasan_check_write+0x3c/0x50\n   _raw_spin_lock+0xa8/0x150\n   binder_deferred_func+0x5e0/0x9b0\n   process_one_work+0x38c/0x5f0\n   worker_thread+0x9c/0x694\n   kthread+0x188/0x190\n   ret_from_fork+0x10/0x20"
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: binder: arreglo UAF de ref-&gt;proc causado por condición de ejecución Una transacción de tipo BINDER_TYPE_WEAK_HANDLE puede fallar al incrementar la referencia para un nodo. En este caso, el proc objetivo normalmente libera la referencia fallida al cerrar como se espera. Sin embargo, si el objetivo está muriendo en paralelo la llamada competirá con binder_deferred_release(), por lo que el objetivo podría haber liberado todas sus referencias por ahora dejando la limpieza de la nueva referencia fallida sin manejar. La transacción entonces termina y el proc objetivo se libera haciendo que ref-&gt;proc ahora sea un puntero colgante. Más tarde, ref-&gt;node se cierra e intentamos tomar spin_lock(&amp;ref-&gt;proc-&gt;inner_lock), lo que lleva al error de Use-After-Free reportado a continuación. Vamos a arreglar esto limpiando la referencia fallida en el acto en lugar de depender de que el objetivo lo haga. ====================================================================== ERROR: KASAN: Use-After-Free en _raw_spin_lock+0xa8/0x150 Escritura de tamaño 4 en la dirección ffff5ca207094238 por la tarea kworker/1:0/590 CPU: 1 PID: 590 Comm: kworker/1:0 No contaminado 5.19.0-rc8 #10 Nombre del hardware: linux,dummy-virt (DT) Cola de trabajo: eventos binder_deferred_func Rastreo de llamadas: dump_backtrace.part.0+0x1d0/0x1e0 show_stack+0x18/0x70 dump_stack_lvl+0x68/0x84 print_report+0x2e4/0x61c kasan_report+0xa4/0x110 kasan_check_range+0xfc/0x1a4 __kasan_check_write+0x3c/0x50 _raw_spin_lock+0xa8/0x150 binder_deferred_func+0x5e0/0x9b0 process_one_work+0x38c/0x5f0 worker_thread+0x9c/0x694 kthread+0x188/0x190 ret_from_fork+0x10/0x20 "
    }
  ],
  "lastModified": "2026-08-04T10:18:00.300",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "90B977E0-CD57-437D-AF5E-63F57E8BCCFF",
              "versionEndExcluding": "4.14.293"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "253D30F5-3734-4663-883A-288786D3B66E",
              "versionEndExcluding": "4.19.258",
              "versionStartIncluding": "4.15"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "4C373116-9E23-44BA-A6B7-87C8BF5C3B85",
              "versionEndExcluding": "5.4.213",
              "versionStartIncluding": "4.20"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "D44AD643-5591-432E-BD41-C2C737F54AC0",
              "versionEndExcluding": "5.10.142",
              "versionStartIncluding": "5.5"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "52AE7E2B-7BE3-4B8A-89CC-AB62434899A3",
              "versionEndExcluding": "5.15.66",
              "versionStartIncluding": "5.11"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7FEC7656-4CE2-424C-8830-EDB160E701C8",
              "versionEndExcluding": "5.19.8",
              "versionStartIncluding": "5.16"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc1:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "E8BD11A3-8643-49B6-BADE-5029A0117325"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc2:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "5F0AD220-F6A9-4012-8636-155F1B841FAD"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc3:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "A46498B3-78E1-4623-AAE1-94D29A42BE4E"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}