CVE-2023-53726

Estado: AplazadaAlta (7.1)—

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

arm64: csum: Fix OoB access in IP checksum code for negative lengths

Although commit c2c24edb1d9c ("arm64: csum: Fix pathological zero-length calls") added an early return for zero-length input, syzkaller has popped up with an example of a _negative_ length which causes an undefined shift and an out-of-bounds read:

Extend the early return to reject negative lengths as well, aligning our implementation with the generic code in lib/checksum.c

Detalles técnicos trazas, registros y código del informe original

 | BUG: KASAN: slab-out-of-bounds in do_csum+0x44/0x254 arch/arm64/lib/csum.c:39
 | Read of size 4294966928 at addr ffff0000d7ac0170 by task syz-executor412/5975
 |
 | CPU: 0 PID: 5975 Comm: syz-executor412 Not tainted 6.4.0-rc4-syzkaller-g908f31f2a05b #0
 | Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
 | Call trace:
 |  dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233
 |  show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240
 |  __dump_stack lib/dump_stack.c:88 [inline]
 |  dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106
 |  print_address_description mm/kasan/report.c:351 [inline]
 |  print_report+0x174/0x514 mm/kasan/report.c:462
 |  kasan_report+0xd4/0x130 mm/kasan/report.c:572
 |  kasan_check_range+0x264/0x2a4 mm/kasan/generic.c:187
 |  __kasan_check_read+0x20/0x30 mm/kasan/shadow.c:31
 |  do_csum+0x44/0x254 arch/arm64/lib/csum.c:39
 |  csum_partial+0x30/0x58 lib/checksum.c:128
 |  gso_make_checksum include/linux/skbuff.h:4928 [inline]
 |  __udp_gso_segment+0xaf4/0x1bc4 net/ipv4/udp_offload.c:332
 |  udp6_ufo_fragment+0x540/0xca0 net/ipv6/udp_offload.c:47
 |  ipv6_gso_segment+0x5cc/0x1760 net/ipv6/ip6_offload.c:119
 |  skb_mac_gso_segment+0x2b4/0x5b0 net/core/gro.c:141
 |  __skb_gso_segment+0x250/0x3d0 net/core/dev.c:3401
 |  skb_gso_segment include/linux/netdevice.h:4859 [inline]
 |  validate_xmit_skb+0x364/0xdbc net/core/dev.c:3659
 |  validate_xmit_skb_list+0x94/0x130 net/core/dev.c:3709
 |  sch_direct_xmit+0xe8/0x548 net/sched/sch_generic.c:327
 |  __dev_xmit_skb net/core/dev.c:3805 [inline]
 |  __dev_queue_xmit+0x147c/0x3318 net/core/dev.c:4210
 |  dev_queue_xmit include/linux/netdevice.h:3085 [inline]
 |  packet_xmit+0x6c/0x318 net/packet/af_packet.c:276
 |  packet_snd net/packet/af_packet.c:3081 [inline]
 |  packet_sendmsg+0x376c/0x4c98 net/packet/af_packet.c:3113
 |  sock_sendmsg_nosec net/socket.c:724 [inline]
 |  sock_sendmsg net/socket.c:747 [inline]
 |  __sys_sendto+0x3b4/0x538 net/socket.c:2144

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Puntuación base: 7.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.15%
Percentil entre todas las CVEs puntuadas: 4
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 escalation75 %
Impacto principalT1499.004 Application or System Exploitationimpact70 %
Impacto secundarioT1005 Data from Local Systemcollection60 %

Vulnerabilidad local (AV:L/PR:L) que permite acceso fuera de límites en memoria kernel vía parámetro negativo en csum_partial, causando lectura masiva de datos y DoS; requiere privilegios locales.

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-2023-53726",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.1,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.2,
        "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": "5777eaed566a1d63e344d3dd8f2b5e33be20643e",
              "lessThan": "5a85727239a23de1cc8d93985f1056308128f3e2",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "5777eaed566a1d63e344d3dd8f2b5e33be20643e",
              "lessThan": "9a43563cfd6b9200ff2f76b3f9fcdcb217ceb523",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "5777eaed566a1d63e344d3dd8f2b5e33be20643e",
              "lessThan": "ba0b46166b8e547024d02345a68b747841931ad2",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "5777eaed566a1d63e344d3dd8f2b5e33be20643e",
              "lessThan": "a5ad2f87d8e74e351d3f500ad9d5b3a5653e1c6f",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "5777eaed566a1d63e344d3dd8f2b5e33be20643e",
              "lessThan": "fcdf904e866de0e3715835e50409fda3b2590527",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "5777eaed566a1d63e344d3dd8f2b5e33be20643e",
              "lessThan": "8bd795fedb8450ecbef18eeadbd23ed8fc7630f5",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "arch/arm64/lib/csum.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.6"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "5.6",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.10.195",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.132",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.53",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.4.16",
              "versionType": "semver",
              "lessThanOrEqual": "6.4.*"
            },
            {
              "status": "unaffected",
              "version": "6.5.3",
              "versionType": "semver",
              "lessThanOrEqual": "6.5.*"
            },
            {
              "status": "unaffected",
              "version": "6.6",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "arch/arm64/lib/csum.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2025-10-22T14:15:47.837",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/5a85727239a23de1cc8d93985f1056308128f3e2",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8bd795fedb8450ecbef18eeadbd23ed8fc7630f5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9a43563cfd6b9200ff2f76b3f9fcdcb217ceb523",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a5ad2f87d8e74e351d3f500ad9d5b3a5653e1c6f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ba0b46166b8e547024d02345a68b747841931ad2",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/fcdf904e866de0e3715835e50409fda3b2590527",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Deferred",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64: csum: Fix OoB access in IP checksum code for negative lengths\n\nAlthough commit c2c24edb1d9c (\"arm64: csum: Fix pathological zero-length\ncalls\") added an early return for zero-length input, syzkaller has\npopped up with an example of a _negative_ length which causes an\nundefined shift and an out-of-bounds read:\n\n | BUG: KASAN: slab-out-of-bounds in do_csum+0x44/0x254 arch/arm64/lib/csum.c:39\n | Read of size 4294966928 at addr ffff0000d7ac0170 by task syz-executor412/5975\n |\n | CPU: 0 PID: 5975 Comm: syz-executor412 Not tainted 6.4.0-rc4-syzkaller-g908f31f2a05b #0\n | Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023\n | Call trace:\n |  dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233\n |  show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240\n |  __dump_stack lib/dump_stack.c:88 [inline]\n |  dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106\n |  print_address_description mm/kasan/report.c:351 [inline]\n |  print_report+0x174/0x514 mm/kasan/report.c:462\n |  kasan_report+0xd4/0x130 mm/kasan/report.c:572\n |  kasan_check_range+0x264/0x2a4 mm/kasan/generic.c:187\n |  __kasan_check_read+0x20/0x30 mm/kasan/shadow.c:31\n |  do_csum+0x44/0x254 arch/arm64/lib/csum.c:39\n |  csum_partial+0x30/0x58 lib/checksum.c:128\n |  gso_make_checksum include/linux/skbuff.h:4928 [inline]\n |  __udp_gso_segment+0xaf4/0x1bc4 net/ipv4/udp_offload.c:332\n |  udp6_ufo_fragment+0x540/0xca0 net/ipv6/udp_offload.c:47\n |  ipv6_gso_segment+0x5cc/0x1760 net/ipv6/ip6_offload.c:119\n |  skb_mac_gso_segment+0x2b4/0x5b0 net/core/gro.c:141\n |  __skb_gso_segment+0x250/0x3d0 net/core/dev.c:3401\n |  skb_gso_segment include/linux/netdevice.h:4859 [inline]\n |  validate_xmit_skb+0x364/0xdbc net/core/dev.c:3659\n |  validate_xmit_skb_list+0x94/0x130 net/core/dev.c:3709\n |  sch_direct_xmit+0xe8/0x548 net/sched/sch_generic.c:327\n |  __dev_xmit_skb net/core/dev.c:3805 [inline]\n |  __dev_queue_xmit+0x147c/0x3318 net/core/dev.c:4210\n |  dev_queue_xmit include/linux/netdevice.h:3085 [inline]\n |  packet_xmit+0x6c/0x318 net/packet/af_packet.c:276\n |  packet_snd net/packet/af_packet.c:3081 [inline]\n |  packet_sendmsg+0x376c/0x4c98 net/packet/af_packet.c:3113\n |  sock_sendmsg_nosec net/socket.c:724 [inline]\n |  sock_sendmsg net/socket.c:747 [inline]\n |  __sys_sendto+0x3b4/0x538 net/socket.c:2144\n\nExtend the early return to reject negative lengths as well, aligning our\nimplementation with the generic code in lib/checksum.c"
    }
  ],
  "lastModified": "2026-08-04T10:19:19.157",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}