CVE-2023-53485

Estado: ModificadaAlta (7.8)—

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

fs: jfs: Fix UBSAN: array-index-out-of-bounds in dbAllocDmapLev

Syzkaller reported the following issue:

The bug occurs when the dbAllocDmapLev()function attempts to access dp->tree.stree[leafidx + LEAFIND] while the leafidx value is negative.

To rectify this, the patch introduces a safeguard within the dbAllocDmapLev() function. A check has been added to verify if leafidx is negative. If it is, the function immediately returns an I/O error, preventing any further execution that could potentially cause harm.

Tested via syzbot.

Detalles técnicos trazas, registros y código del informe original

UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:1965:6
index -84 is out of range for type 's8[341]' (aka 'signed char[341]')
CPU: 1 PID: 4995 Comm: syz-executor146 Not tainted 6.4.0-rc6-syzkaller-00037-gb6dad5178cea #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 ubsan_epilogue lib/ubsan.c:217 [inline]
 __ubsan_handle_out_of_bounds+0x11c/0x150 lib/ubsan.c:348
 dbAllocDmapLev+0x3e5/0x430 fs/jfs/jfs_dmap.c:1965
 dbAllocCtl+0x113/0x920 fs/jfs/jfs_dmap.c:1809
 dbAllocAG+0x28f/0x10b0 fs/jfs/jfs_dmap.c:1350
 dbAlloc+0x658/0xca0 fs/jfs/jfs_dmap.c:874
 dtSplitUp fs/jfs/jfs_dtree.c:974 [inline]
 dtInsert+0xda7/0x6b00 fs/jfs/jfs_dtree.c:863
 jfs_create+0x7b6/0xbb0 fs/jfs/namei.c:137
 lookup_open fs/namei.c:3492 [inline]
 open_last_lookups fs/namei.c:3560 [inline]
 path_openat+0x13df/0x3170 fs/namei.c:3788
 do_filp_open+0x234/0x490 fs/namei.c:3818
 do_sys_openat2+0x13f/0x500 fs/open.c:1356
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0x247/0x290 fs/open.c:1383
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f1f4e33f7e9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc21129578 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1f4e33f7e9
RDX: 000000000000275a RSI: 0000000020000040 RDI: 00000000ffffff9c
RBP: 00007f1f4e2ff080 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1f4e2ff110
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

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: 7
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 %
Impacto secundarioT1565.001 Stored Data Manipulationimpact60 %

Vulnerabilidad local (AV:L/PR:L) en kernel JFS que causa out-of-bounds array access. Permite escalada de privilegios o denegación de servicio mediante operaciones de archivo malformadas.

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 Restrict File and Directory Permissions Remote Data Storage Filter Network Traffic Execution Prevention Encrypt Sensitive Information

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-129

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2023-53485",
  "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": 7.8,
          "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": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "lessThan": "0d9e678a82915633b99603f744e7735d1a673d72",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "lessThan": "53b0a362aca2583729e8ca2936ca657ff3247d88",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "lessThan": "6e7d9d76e5654bcdd3cdb7c9441a8113428ecebb",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "lessThan": "911b48eec45152822bccf45cd3563b48256b1520",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "lessThan": "39f6292d75959e8accac0b3e24090094ba0824e9",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "lessThan": "bdf07ab1595b613b03f32dbb5cb379edfa1a7334",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "lessThan": "f2af019091f904ca08b3572ab0111238ad6d17b3",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "lessThan": "4e302336d5ca1767a06beee7596a72d3bdc8d983",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "fs/jfs/jfs_dmap.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.12"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "2.6.12",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "4.14.324",
              "versionType": "semver",
              "lessThanOrEqual": "4.14.*"
            },
            {
              "status": "unaffected",
              "version": "4.19.293",
              "versionType": "semver",
              "lessThanOrEqual": "4.19.*"
            },
            {
              "status": "unaffected",
              "version": "5.4.255",
              "versionType": "semver",
              "lessThanOrEqual": "5.4.*"
            },
            {
              "status": "unaffected",
              "version": "5.10.192",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.123",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.42",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.4.7",
              "versionType": "semver",
              "lessThanOrEqual": "6.4.*"
            },
            {
              "status": "unaffected",
              "version": "6.5",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "fs/jfs/jfs_dmap.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2025-10-01T12:15:51.330",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0d9e678a82915633b99603f744e7735d1a673d72",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/39f6292d75959e8accac0b3e24090094ba0824e9",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4e302336d5ca1767a06beee7596a72d3bdc8d983",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/53b0a362aca2583729e8ca2936ca657ff3247d88",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6e7d9d76e5654bcdd3cdb7c9441a8113428ecebb",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/911b48eec45152822bccf45cd3563b48256b1520",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/bdf07ab1595b613b03f32dbb5cb379edfa1a7334",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f2af019091f904ca08b3572ab0111238ad6d17b3",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-129"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs: jfs: Fix UBSAN: array-index-out-of-bounds in dbAllocDmapLev\n\nSyzkaller reported the following issue:\n\nUBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:1965:6\nindex -84 is out of range for type 's8[341]' (aka 'signed char[341]')\nCPU: 1 PID: 4995 Comm: syz-executor146 Not tainted 6.4.0-rc6-syzkaller-00037-gb6dad5178cea #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023\nCall Trace:\n <TASK>\n __dump_stack lib/dump_stack.c:88 [inline]\n dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106\n ubsan_epilogue lib/ubsan.c:217 [inline]\n __ubsan_handle_out_of_bounds+0x11c/0x150 lib/ubsan.c:348\n dbAllocDmapLev+0x3e5/0x430 fs/jfs/jfs_dmap.c:1965\n dbAllocCtl+0x113/0x920 fs/jfs/jfs_dmap.c:1809\n dbAllocAG+0x28f/0x10b0 fs/jfs/jfs_dmap.c:1350\n dbAlloc+0x658/0xca0 fs/jfs/jfs_dmap.c:874\n dtSplitUp fs/jfs/jfs_dtree.c:974 [inline]\n dtInsert+0xda7/0x6b00 fs/jfs/jfs_dtree.c:863\n jfs_create+0x7b6/0xbb0 fs/jfs/namei.c:137\n lookup_open fs/namei.c:3492 [inline]\n open_last_lookups fs/namei.c:3560 [inline]\n path_openat+0x13df/0x3170 fs/namei.c:3788\n do_filp_open+0x234/0x490 fs/namei.c:3818\n do_sys_openat2+0x13f/0x500 fs/open.c:1356\n do_sys_open fs/open.c:1372 [inline]\n __do_sys_openat fs/open.c:1388 [inline]\n __se_sys_openat fs/open.c:1383 [inline]\n __x64_sys_openat+0x247/0x290 fs/open.c:1383\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\nRIP: 0033:0x7f1f4e33f7e9\nCode: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007ffc21129578 EFLAGS: 00000246 ORIG_RAX: 0000000000000101\nRAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1f4e33f7e9\nRDX: 000000000000275a RSI: 0000000020000040 RDI: 00000000ffffff9c\nRBP: 00007f1f4e2ff080 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 00007f1f4e2ff110\nR13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000\n </TASK>\n\nThe bug occurs when the dbAllocDmapLev()function attempts to access\ndp->tree.stree[leafidx + LEAFIND] while the leafidx value is negative.\n\nTo rectify this, the patch introduces a safeguard within the\ndbAllocDmapLev() function. A check has been added to verify if leafidx is\nnegative. If it is, the function immediately returns an I/O error, preventing\nany further execution that could potentially cause harm.\n\nTested via syzbot."
    }
  ],
  "lastModified": "2026-08-04T10:19:08.413",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "A4471ACF-EC60-49C1-96FF-B301856C131F",
              "versionEndExcluding": "4.14.324",
              "versionStartIncluding": "2.6.12.1"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "39603052-E341-4096-8535-38D44A60E845",
              "versionEndExcluding": "4.19.293",
              "versionStartIncluding": "4.15"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "1379E40A-2AC3-484E-929A-7F46B6C3B521",
              "versionEndExcluding": "5.4.255",
              "versionStartIncluding": "4.20"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "9396FFDC-6A0D-44B7-9368-21B456F6D4AE",
              "versionEndExcluding": "5.10.192",
              "versionStartIncluding": "5.5"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "372C0BAA-44F5-4829-A7B0-E4924B682DA4",
              "versionEndExcluding": "5.15.123",
              "versionStartIncluding": "5.11"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "6E769E6A-7EEF-4FA8-BF41-6CA1CE537361",
              "versionEndExcluding": "6.1.42",
              "versionStartIncluding": "5.16"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "60A1A1ED-EA6C-42F6-80D3-3316DC7608C7",
              "versionEndExcluding": "6.4.7",
              "versionStartIncluding": "6.2"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "6F62EECE-8FB1-4D57-85D8-CB9E23CF313C"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "4F76C298-81DC-43E4-8FC9-DC005A2116EF"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "0AB349B2-3F78-4197-882B-90ADB3BF645A"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "6AC88830-A9BC-4607-B572-A4B502FC9FD0"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "476CB3A5-D022-4F13-AAEF-CB6A5785516A"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}