CVE-2023-53862

Estado: AplazadaAlta (7.8)—

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

hfs: fix missing hfs_bnode_get() in __hfs_bnode_create

Syzbot found a kernel BUG in hfs_bnode_put():

The BUG_ON() is triggered at here:

/* Dispose of resources used by a node */ void hfs_bnode_put(struct hfs_bnode *node) { if (node) { <skipped> BUG_ON(!atomic_read(&node->refcnt)); <- we have issue here!!!! <skipped> } }

By tracing the refcnt, I found the node is created by hfs_bmap_alloc() with refcnt 1. Then the node is used by hfs_btree_write(). There is a missing of hfs_bnode_get() after find the node. The issue happened in following path:

Detalles técnicos trazas, registros y código del informe original

 kernel BUG at fs/hfs/bnode.c:466!
 invalid opcode: 0000 [#1] PREEMPT SMP KASAN
 CPU: 0 PID: 3634 Comm: kworker/u4:5 Not tainted 6.1.0-rc7-syzkaller-00190-g97ee9d1c1696 #0
 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
 Workqueue: writeback wb_workfn (flush-7:0)
 RIP: 0010:hfs_bnode_put+0x46f/0x480 fs/hfs/bnode.c:466
 Code: 8a 80 ff e9 73 fe ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c a0 fe ff ff 48 89 df e8 db 8a 80 ff e9 93 fe ff ff e8 a1 68 2c ff <0f> 0b e8 9a 68 2c ff 0f 0b 0f 1f 84 00 00 00 00 00 55 41 57 41 56
 RSP: 0018:ffffc90003b4f258 EFLAGS: 00010293
 RAX: ffffffff825e318f RBX: 0000000000000000 RCX: ffff8880739dd7c0
 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
 RBP: ffffc90003b4f430 R08: ffffffff825e2d9b R09: ffffed10045157d1
 R10: ffffed10045157d1 R11: 1ffff110045157d0 R12: ffff8880228abe80
 R13: ffff88807016c000 R14: dffffc0000000000 R15: ffff8880228abe00
 FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007fa6ebe88718 CR3: 000000001e93d000 CR4: 00000000003506f0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  <TASK>
  hfs_write_inode+0x1bc/0xb40
  write_inode fs/fs-writeback.c:1440 [inline]
  __writeback_single_inode+0x4d6/0x670 fs/fs-writeback.c:1652
  writeback_sb_inodes+0xb3b/0x18f0 fs/fs-writeback.c:1878
  __writeback_inodes_wb+0x125/0x420 fs/fs-writeback.c:1949
  wb_writeback+0x440/0x7b0 fs/fs-writeback.c:2054
  wb_check_start_all fs/fs-writeback.c:2176 [inline]
  wb_do_writeback fs/fs-writeback.c:2202 [inline]
  wb_workfn+0x827/0xef0 fs/fs-writeback.c:2235
  process_one_work+0x877/0xdb0 kernel/workqueue.c:2289
  worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
  kthread+0x266/0x300 kernel/kthread.c:376
  ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
  </TASK>

<alloc>
 hfs_bmap_alloc
   hfs_bnode_find
     __hfs_bnode_create   <- allocate a new node with refcnt 1.
   hfs_bnode_put          <- decrease the refcnt

<write>
 hfs_btree_write
   hfs_bnode_find
     __hfs_bnode_create
       hfs_bnode_findhash <- find the node without refcnt increased.
   hfs_bnode_put	  <- trigger the BUG_ON() since refcnt is 0.

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: 0.19%
Percentil entre todas las CVEs puntuadas: 8
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 escalation85 %
Impacto principalT1499.004 Application or System Exploitationimpact75 %

Vulnerabilidad local (AV:L/PR:L) sin interacción en kernel HFS. Genera DoS por kernel BUG_ON() en referencia de nodos, impactando disponibilidad del sistema.

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 Program Filter Network Traffic Execution Prevention Application Isolation and Sandboxing Exploit Protection Update 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 Kernel^AI

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2023-53862",
  "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": [
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      "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": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "lessThan": "062af3e9930762d1fd22946748d34e0d859e4a8e",
              "versionType": "git"
            },
            {
              "status": "affected",
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              "versionType": "git"
            },
            {
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              "lessThan": "eda6879272e4df5456afc36642052ea066f58410",
              "versionType": "git"
            },
            {
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              "versionType": "git"
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            {
              "status": "affected",
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              "lessThan": "2cab8db14566cf6a516c1f103a60cf6b7f54b1e5",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "lessThan": "8140cdc57bc5844cd5e1392673ec2dbf8fdc6940",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "lessThan": "38d72e6604b9f96dffcc0565090cc01622a37b2a",
              "versionType": "git"
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            {
              "status": "affected",
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              "lessThan": "a9dc087fd3c484fd1ed18c5efb290efaaf44ce03",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "fs/hfs/bnode.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
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              "version": "2.6.12"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "2.6.12",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "4.14.308",
              "versionType": "semver",
              "lessThanOrEqual": "4.14.*"
            },
            {
              "status": "unaffected",
              "version": "4.19.276",
              "versionType": "semver",
              "lessThanOrEqual": "4.19.*"
            },
            {
              "status": "unaffected",
              "version": "5.4.235",
              "versionType": "semver",
              "lessThanOrEqual": "5.4.*"
            },
            {
              "status": "unaffected",
              "version": "5.10.173",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.99",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.16",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.2.3",
              "versionType": "semver",
              "lessThanOrEqual": "6.2.*"
            },
            {
              "status": "unaffected",
              "version": "6.3",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "fs/hfs/bnode.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2025-12-09T16:17:26.970",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/062af3e9930762d1fd22946748d34e0d859e4a8e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2cab8db14566cf6a516c1f103a60cf6b7f54b1e5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/38d72e6604b9f96dffcc0565090cc01622a37b2a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/3a9065a33988c02789722be612f7c42fb8ebbb22",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8140cdc57bc5844cd5e1392673ec2dbf8fdc6940",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a9dc087fd3c484fd1ed18c5efb290efaaf44ce03",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/dc9f78b6d254427a06e568f2887b1011ef3143ef",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/eda6879272e4df5456afc36642052ea066f58410",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Deferred",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nhfs: fix missing hfs_bnode_get() in __hfs_bnode_create\n\nSyzbot found a kernel BUG in hfs_bnode_put():\n\n kernel BUG at fs/hfs/bnode.c:466!\n invalid opcode: 0000 [#1] PREEMPT SMP KASAN\n CPU: 0 PID: 3634 Comm: kworker/u4:5 Not tainted 6.1.0-rc7-syzkaller-00190-g97ee9d1c1696 #0\n Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022\n Workqueue: writeback wb_workfn (flush-7:0)\n RIP: 0010:hfs_bnode_put+0x46f/0x480 fs/hfs/bnode.c:466\n Code: 8a 80 ff e9 73 fe ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c a0 fe ff ff 48 89 df e8 db 8a 80 ff e9 93 fe ff ff e8 a1 68 2c ff <0f> 0b e8 9a 68 2c ff 0f 0b 0f 1f 84 00 00 00 00 00 55 41 57 41 56\n RSP: 0018:ffffc90003b4f258 EFLAGS: 00010293\n RAX: ffffffff825e318f RBX: 0000000000000000 RCX: ffff8880739dd7c0\n RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000\n RBP: ffffc90003b4f430 R08: ffffffff825e2d9b R09: ffffed10045157d1\n R10: ffffed10045157d1 R11: 1ffff110045157d0 R12: ffff8880228abe80\n R13: ffff88807016c000 R14: dffffc0000000000 R15: ffff8880228abe00\n FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007fa6ebe88718 CR3: 000000001e93d000 CR4: 00000000003506f0\n DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n Call Trace:\n  <TASK>\n  hfs_write_inode+0x1bc/0xb40\n  write_inode fs/fs-writeback.c:1440 [inline]\n  __writeback_single_inode+0x4d6/0x670 fs/fs-writeback.c:1652\n  writeback_sb_inodes+0xb3b/0x18f0 fs/fs-writeback.c:1878\n  __writeback_inodes_wb+0x125/0x420 fs/fs-writeback.c:1949\n  wb_writeback+0x440/0x7b0 fs/fs-writeback.c:2054\n  wb_check_start_all fs/fs-writeback.c:2176 [inline]\n  wb_do_writeback fs/fs-writeback.c:2202 [inline]\n  wb_workfn+0x827/0xef0 fs/fs-writeback.c:2235\n  process_one_work+0x877/0xdb0 kernel/workqueue.c:2289\n  worker_thread+0xb14/0x1330 kernel/workqueue.c:2436\n  kthread+0x266/0x300 kernel/kthread.c:376\n  ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306\n  </TASK>\n\nThe BUG_ON() is triggered at here:\n\n/* Dispose of resources used by a node */\nvoid hfs_bnode_put(struct hfs_bnode *node)\n{\n\tif (node) {\n \t\t<skipped>\n \t\tBUG_ON(!atomic_read(&node->refcnt)); <- we have issue here!!!!\n \t\t<skipped>\n \t}\n}\n\nBy tracing the refcnt, I found the node is created by hfs_bmap_alloc()\nwith refcnt 1.  Then the node is used by hfs_btree_write().  There is a\nmissing of hfs_bnode_get() after find the node.  The issue happened in\nfollowing path:\n\n<alloc>\n hfs_bmap_alloc\n   hfs_bnode_find\n     __hfs_bnode_create   <- allocate a new node with refcnt 1.\n   hfs_bnode_put          <- decrease the refcnt\n\n<write>\n hfs_btree_write\n   hfs_bnode_find\n     __hfs_bnode_create\n       hfs_bnode_findhash <- find the node without refcnt increased.\n   hfs_bnode_put\t  <- trigger the BUG_ON() since refcnt is 0."
    }
  ],
  "lastModified": "2026-08-04T10:19:24.310",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}