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CVE-2026-68284

Estado: RecibidaAlta (7.8)—

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

bpf, sockmap: Fix cork use-after-free in tcp_bpf_sendmsg()

tcp_bpf_sendmsg() keeps msg_tx across sk_stream_wait_memory(), which drops and reacquires the socket lock. Its error path tries to decide whether msg_tx names the local temporary message by comparing it with the current value of psock->cork.

This comparison is unsafe when two threads send on the same socket:

The stale cork is therefore mistaken for the local temporary message and freed again. KASAN reported:

msg_tx can only name the stack-local tmp or the shared cork. Check for tmp directly so a changed psock->cork cannot turn a shared message into an apparent local one.

Detalles técnicos trazas, registros y código del informe original
  Thread A                         Thread B
  msg_tx = psock->cork
  sk_msg_alloc() fails
  sk_stream_wait_memory()
    releases the socket lock      acquires the socket lock
                                  completes the cork
                                  psock->cork = NULL
                                  frees the cork
    reacquires the socket lock
  msg_tx != psock->cork
  sk_msg_free(msg_tx)

  BUG: KASAN: slab-use-after-free in sk_msg_free+0x49/0x50
  Read of size 4 at addr ffff88810c908800 by task poc/90
  Call Trace:
   sk_msg_free+0x49/0x50
   tcp_bpf_sendmsg+0x14f5/0x1cc0
   __sys_sendto+0x32c/0x3a0
   __x64_sys_sendto+0xdb/0x1b0
  Allocated by task 89:
   __kasan_kmalloc+0x8f/0xa0
   tcp_bpf_sendmsg+0x16b3/0x1cc0
  Freed by task 91:
   __kasan_slab_free+0x43/0x70
   kfree+0x131/0x3c0
   tcp_bpf_sendmsg+0xec3/0x1cc0

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 en kernel con AV:L/PR:L que permite escalada de privilegios; impacto DoS por corrupción de memoria y manipulación de datos de socket en envío.

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 ProgramExecution PreventionApplication Isolation and SandboxingExploit ProtectionUpdate 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 KernelAI

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-68284",
  "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": "604326b41a6fb9b4a78b6179335decee0365cd8c",
              "lessThan": "0688e6fe599d2d39147ae9ece97944c6e1815ebf",
              "versionType": "git"
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            {
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              "versionType": "git"
            },
            {
              "status": "affected",
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              "lessThan": "54be47e7cbb936429c3bbdfc526ea943954aaf80",
              "versionType": "git"
            },
            {
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              "versionType": "git"
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            {
              "status": "affected",
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              "versionType": "git"
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              "versionType": "git"
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              "lessThan": "2d66a033864e27ab8d5e44cb36f31d9d2413bee4",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "net/ipv4/tcp_bpf.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.20"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "4.20",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.10.265",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.216",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.183",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.148",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.12.101",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "net/ipv4/tcp_bpf.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-08-10T13:20:17.670",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0688e6fe599d2d39147ae9ece97944c6e1815ebf",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2d66a033864e27ab8d5e44cb36f31d9d2413bee4",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    {
      "url": "https://git.kernel.org/stable/c/54be47e7cbb936429c3bbdfc526ea943954aaf80",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/752b1159ed5d0c48fe169a3721b96660a9822aa1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/786d690257ec7a0c839f8710456e444ce3f1348b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b2bcbeabfd843d47468fa095b1bd08ddb90cf616",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cde4d6bcd9b73073c66498f6723c7b364c4dbc18",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ee762f684eefa59de34d9ed93cab08336e834f47",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf, sockmap: Fix cork use-after-free in tcp_bpf_sendmsg()\n\ntcp_bpf_sendmsg() keeps msg_tx across sk_stream_wait_memory(), which\ndrops and reacquires the socket lock.  Its error path tries to decide\nwhether msg_tx names the local temporary message by comparing it with\nthe current value of psock->cork.\n\nThis comparison is unsafe when two threads send on the same socket:\n\n  Thread A                         Thread B\n  msg_tx = psock->cork\n  sk_msg_alloc() fails\n  sk_stream_wait_memory()\n    releases the socket lock      acquires the socket lock\n                                  completes the cork\n                                  psock->cork = NULL\n                                  frees the cork\n    reacquires the socket lock\n  msg_tx != psock->cork\n  sk_msg_free(msg_tx)\n\nThe stale cork is therefore mistaken for the local temporary message\nand freed again.  KASAN reported:\n\n  BUG: KASAN: slab-use-after-free in sk_msg_free+0x49/0x50\n  Read of size 4 at addr ffff88810c908800 by task poc/90\n  Call Trace:\n   sk_msg_free+0x49/0x50\n   tcp_bpf_sendmsg+0x14f5/0x1cc0\n   __sys_sendto+0x32c/0x3a0\n   __x64_sys_sendto+0xdb/0x1b0\n  Allocated by task 89:\n   __kasan_kmalloc+0x8f/0xa0\n   tcp_bpf_sendmsg+0x16b3/0x1cc0\n  Freed by task 91:\n   __kasan_slab_free+0x43/0x70\n   kfree+0x131/0x3c0\n   tcp_bpf_sendmsg+0xec3/0x1cc0\n\nmsg_tx can only name the stack-local tmp or the shared cork. Check for\ntmp directly so a changed psock->cork cannot turn a shared message into\nan apparent local one."
    }
  ],
  "lastModified": "2026-08-19T17:20:40.573",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}