CVE-2023-54303

Status: DeferredHigh (7.8)—

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

bpf: Disable preemption in bpf_perf_event_output

The nesting protection in bpf_perf_event_output relies on disabled preemption, which is guaranteed for kprobes and tracepoints.

However bpf_perf_event_output can be also called from uprobes context through bpf_prog_run_array_sleepable function which disables migration, but keeps preemption enabled.

This can cause task to be preempted by another one inside the nesting protection and lead eventually to two tasks using same perf_sample_data buffer and cause crashes like:

Fixing this by disabling preemption in bpf_perf_event_output.

Technical details traces, logs and code from the original report

  kernel tried to execute NX-protected page - exploit attempt? (uid: 0)
  BUG: unable to handle page fault for address: ffffffff82be3eea
  ...
  Call Trace:
   ? __die+0x1f/0x70
   ? page_fault_oops+0x176/0x4d0
   ? exc_page_fault+0x132/0x230
   ? asm_exc_page_fault+0x22/0x30
   ? perf_output_sample+0x12b/0x910
   ? perf_event_output+0xd0/0x1d0
   ? bpf_perf_event_output+0x162/0x1d0
   ? bpf_prog_c6271286d9a4c938_krava1+0x76/0x87
   ? __uprobe_perf_func+0x12b/0x540
   ? uprobe_dispatcher+0x2c4/0x430
   ? uprobe_notify_resume+0x2da/0xce0
   ? atomic_notifier_call_chain+0x7b/0x110
   ? exit_to_user_mode_prepare+0x13e/0x290
   ? irqentry_exit_to_user_mode+0x5/0x30
   ? asm_exc_int3+0x35/0x40

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Base score: 7.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.15%
Percentile among all scored CVEs: 4
Score date: 10/6/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1068 Exploitation for Privilege Escalationprivilege escalation85 %
Primary impactT1499.004 Application or System Exploitationimpact75 %
Secondary impactT1548 Abuse Elevation Control Mechanismprivilege escalation60 %

Vulnerabilidad de escalada de privilegios en kernel Linux (AV:L, PR:L) que causa race condition en bpf_perf_event_output. Permite DoS por crash y potencial ejecución de código en contexto de kernel mediante preemption race.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Execution Prevention Update Software User Account Management Threat Intelligence Program Restrict File and Directory Permissions Privileged Account Management

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Linux — Linux Kernel^AI

References

Raw JSON (NVD)

Show

{
  "id": "CVE-2023-54303",
  "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": "8c7dcb84e3b744b2b70baa7a44a9b1881c33a9c9",
              "lessThan": "3654ed5daf492463c3faa434c7000d45c2da2ace",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "8c7dcb84e3b744b2b70baa7a44a9b1881c33a9c9",
              "lessThan": "a0ac32cf61e5a76e2429e486925a52ee41dd75e3",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "8c7dcb84e3b744b2b70baa7a44a9b1881c33a9c9",
              "lessThan": "f2c67a3e60d1071b65848efaa8c3b66c363dd025",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "kernel/trace/bpf_trace.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.0"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "6.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "6.1.45",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.4.10",
              "versionType": "semver",
              "lessThanOrEqual": "6.4.*"
            },
            {
              "status": "unaffected",
              "version": "6.5",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "kernel/trace/bpf_trace.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2025-12-30T13:16:19.437",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/3654ed5daf492463c3faa434c7000d45c2da2ace",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a0ac32cf61e5a76e2429e486925a52ee41dd75e3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f2c67a3e60d1071b65848efaa8c3b66c363dd025",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Deferred",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Disable preemption in bpf_perf_event_output\n\nThe nesting protection in bpf_perf_event_output relies on disabled\npreemption, which is guaranteed for kprobes and tracepoints.\n\nHowever bpf_perf_event_output can be also called from uprobes context\nthrough bpf_prog_run_array_sleepable function which disables migration,\nbut keeps preemption enabled.\n\nThis can cause task to be preempted by another one inside the nesting\nprotection and lead eventually to two tasks using same perf_sample_data\nbuffer and cause crashes like:\n\n  kernel tried to execute NX-protected page - exploit attempt? (uid: 0)\n  BUG: unable to handle page fault for address: ffffffff82be3eea\n  ...\n  Call Trace:\n   ? __die+0x1f/0x70\n   ? page_fault_oops+0x176/0x4d0\n   ? exc_page_fault+0x132/0x230\n   ? asm_exc_page_fault+0x22/0x30\n   ? perf_output_sample+0x12b/0x910\n   ? perf_event_output+0xd0/0x1d0\n   ? bpf_perf_event_output+0x162/0x1d0\n   ? bpf_prog_c6271286d9a4c938_krava1+0x76/0x87\n   ? __uprobe_perf_func+0x12b/0x540\n   ? uprobe_dispatcher+0x2c4/0x430\n   ? uprobe_notify_resume+0x2da/0xce0\n   ? atomic_notifier_call_chain+0x7b/0x110\n   ? exit_to_user_mode_prepare+0x13e/0x290\n   ? irqentry_exit_to_user_mode+0x5/0x30\n   ? asm_exc_int3+0x35/0x40\n\nFixing this by disabling preemption in bpf_perf_event_output."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nbpf: Deshabilitar la preferencia en bpf_perf_event_output\n\nLa protección de anidamiento en bpf_perf_event_output se basa en la preferencia deshabilitada, lo cual está garantizado para kprobes y tracepoints.\n\nSin embargo, bpf_perf_event_output también puede ser llamado desde el contexto de uprobes a través de la función bpf_prog_run_array_sleepable que deshabilita la migración, pero mantiene la preferencia habilitada.\n\nEsto puede causar que una tarea sea preferida por otra dentro de la protección de anidamiento y eventualmente llevar a que dos tareas usen el mismo búfer perf_sample_data y causen fallos como:\n\n  el kernel intentó ejecutar una página protegida por NX - ¿intento de exploit? (uid: 0)\n  BUG: no se puede manejar el fallo de página para la dirección: ffffffff82be3eea\n  ...\n  Rastro de Llamada:\n   ? __die+0x1f/0x70\n   ? page_fault_oops+0x176/0x4d0\n   ? exc_page_fault+0x132/0x230\n   ? asm_exc_page_fault+0x22/0x30\n   ? perf_output_sample+0x12b/0x910\n   ? perf_event_output+0xd0/0x1d0\n   ? bpf_perf_event_output+0x162/0x1d0\n   ? bpf_prog_c6271286d9a4c938_krava1+0x76/0x87\n   ? __uprobe_perf_func+0x12b/0x540\n   ? uprobe_dispatcher+0x2c4/0x430\n   ? uprobe_notify_resume+0x2da/0xce0\n   ? atomic_notifier_call_chain+0x7b/0x110\n   ? exit_to_user_mode_prepare+0x13e/0x290\n   ? irqentry_exit_to_user_mode+0x5/0x30\n   ? asm_exc_int3+0x35/0x40\n\nEsto se soluciona deshabilitando la preferencia en bpf_perf_event_output."
    }
  ],
  "lastModified": "2026-08-04T11:16:39.610",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}