« Volver al listado

CVE-2026-64579

Estado: RecibidaSin puntuar—

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

xfrm: policy: preallocate inexact bins before xfrm_hash_rebuild reinsert

xfrm_hash_rebuild()'s first loop preallocates the bins/chains the reinsert loop needs, so the reinsert (after hlist_del_rcu()) cannot allocate or fail. But its guard is inverted: it skips policies with prefixlen < threshold and preallocates for the rest.

prefixlen < threshold is exactly when policy_hash_bysel() returns NULL and the reinsert takes the allocating xfrm_policy_inexact_insert() path.

Leer descripción completaMostrar menos

So the loop preallocates for the exact policies (which never allocate) and skips the inexact ones, whose bin/node is then allocated GFP_ATOMIC during reinsert. On failure the error path only WARN_ONCE()s and continues, leaving a poisoned bydst node; the next rebuild's hlist_del_rcu() dereferences LIST_POISON2 and takes a GPF. Reachable under memory pressure, deterministic via failslab.

Detalles técnicos trazas, registros y código del informe original
Invert the guard so preallocation covers exactly the reinserted policies;
the reinsert then allocates nothing and cannot fail.

Crash:
  Oops: general protection fault, probably for non-canonical address
  0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI
  KASAN: maybe wild-memory-access in range [0xdead...]
  ...
  Workqueue: events xfrm_hash_rebuild
  RIP: 0010:xfrm_hash_rebuild+0x5b3/0x1190
  RAX: dead000000000122   (LIST_POISON2 + offset)
  ...
  Call Trace:
   hlist_del_rcu (include/linux/rculist.h:599)
   xfrm_hash_rebuild (net/xfrm/xfrm_policy.c:1365)
   process_one_work (kernel/workqueue.c:3322)
   worker_thread (kernel/workqueue.c:3486)
   kthread (kernel/kthread.c:436)
   ret_from_fork (arch/x86/kernel/process.c:158)
   ret_from_fork_asm (arch/x86/entry/entry_64.S:245)
   ...
  Kernel panic - not syncing: Fatal exception in interrupt

CVSS

NVD no ha asignado puntuación CVSS a esta CVE (habitual desde el cambio de política de abril de 2026).

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).

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-2026-64579",
  "cveTags": [],
  "metrics": {},
  "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": "24969facd704a5f0dd8e08da86bf32a9ce972bee",
              "lessThan": "e48f4c3e3df35b34be719d72d737bbeaca77cf0c",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "24969facd704a5f0dd8e08da86bf32a9ce972bee",
              "lessThan": "1cdeed9df1306f1a277e715600772640d63defa9",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "24969facd704a5f0dd8e08da86bf32a9ce972bee",
              "lessThan": "43a4d510523779891cf8eca7ffb4a086b0b5d8bf",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "24969facd704a5f0dd8e08da86bf32a9ce972bee",
              "lessThan": "d9d9cc21cc90014724a14c447e3d587be9447107",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "24969facd704a5f0dd8e08da86bf32a9ce972bee",
              "lessThan": "94c00391a5117530188334f740ce26d3f1256190",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "24969facd704a5f0dd8e08da86bf32a9ce972bee",
              "lessThan": "7acc5ed2f33608a3d83b64f50a5766843b6e2485",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "24969facd704a5f0dd8e08da86bf32a9ce972bee",
              "lessThan": "6aa3796d18a9fda953ad76a62b57bf6c145cb9ef",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "24969facd704a5f0dd8e08da86bf32a9ce972bee",
              "lessThan": "f38f8cce2f7e79775b3db7e8a5eacda04ac908e4",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "net/xfrm/xfrm_policy.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.0"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "5.0",
              "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/xfrm/xfrm_policy.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-08-05T08:16:37.893",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1cdeed9df1306f1a277e715600772640d63defa9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/43a4d510523779891cf8eca7ffb4a086b0b5d8bf",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6aa3796d18a9fda953ad76a62b57bf6c145cb9ef",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7acc5ed2f33608a3d83b64f50a5766843b6e2485",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/94c00391a5117530188334f740ce26d3f1256190",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d9d9cc21cc90014724a14c447e3d587be9447107",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e48f4c3e3df35b34be719d72d737bbeaca77cf0c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f38f8cce2f7e79775b3db7e8a5eacda04ac908e4",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: policy: preallocate inexact bins before xfrm_hash_rebuild reinsert\n\nxfrm_hash_rebuild()'s first loop preallocates the bins/chains the reinsert\nloop needs, so the reinsert (after hlist_del_rcu()) cannot allocate or\nfail. But its guard is inverted: it skips policies with prefixlen <\nthreshold and preallocates for the rest.\n\nprefixlen < threshold is exactly when policy_hash_bysel() returns NULL and\nthe reinsert takes the allocating xfrm_policy_inexact_insert() path. So the\nloop preallocates for the exact policies (which never allocate) and skips\nthe inexact ones, whose bin/node is then allocated GFP_ATOMIC during\nreinsert. On failure the error path only WARN_ONCE()s and continues,\nleaving a poisoned bydst node; the next rebuild's hlist_del_rcu()\ndereferences LIST_POISON2 and takes a GPF. Reachable under memory pressure,\ndeterministic via failslab.\n\nInvert the guard so preallocation covers exactly the reinserted policies;\nthe reinsert then allocates nothing and cannot fail.\n\nCrash:\n  Oops: general protection fault, probably for non-canonical address\n  0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI\n  KASAN: maybe wild-memory-access in range [0xdead...]\n  ...\n  Workqueue: events xfrm_hash_rebuild\n  RIP: 0010:xfrm_hash_rebuild+0x5b3/0x1190\n  RAX: dead000000000122   (LIST_POISON2 + offset)\n  ...\n  Call Trace:\n   hlist_del_rcu (include/linux/rculist.h:599)\n   xfrm_hash_rebuild (net/xfrm/xfrm_policy.c:1365)\n   process_one_work (kernel/workqueue.c:3322)\n   worker_thread (kernel/workqueue.c:3486)\n   kthread (kernel/kthread.c:436)\n   ret_from_fork (arch/x86/kernel/process.c:158)\n   ret_from_fork_asm (arch/x86/entry/entry_64.S:245)\n   ...\n  Kernel panic - not syncing: Fatal exception in interrupt"
    }
  ],
  "lastModified": "2026-08-19T17:20:17.990",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}