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CVE-2021-33624

Estado: ModificadaMedia (4.7)—💥 PoC

En el archivo kernel/bpf/verifier.c en el kernel de Linux versiones anteriores a 5.12.13, una rama puede ser mal predicha (por ejemplo, debido a la confusión de tipos) y, en consecuencia, un programa BPF no privilegiado puede leer ubicaciones de memoria arbitrarias por medio de un ataque de canal lateral, también conocido como CID-9183671af6db

CVSS

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).

💥 Exploits públicos

Hay código de explotación o plantillas de detección públicos. No es lo mismo que explotación activa confirmada (KEV), pero aumenta el riesgo: parchee con prioridad.

⚠️ Las pruebas de concepto de GitHub no están verificadas: algunas son falsas o contienen malware. No las ejecute nunca fuera de un laboratorio aislado.

Tecnologías afectadas (2)

Debian — Debian LinuxLinux — Linux Kernel

CWE

Referencias

JSON original (NVD)

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  "id": "CVE-2021-33624",
  "cveTags": [],
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              "technicalImpact": "partial"
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          "version": "2.0.3",
          "timestamp": "2026-10-08T20:59:43.490156Z"
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          "vectorString": "AV:L/AC:M/Au:N/C:C/I:N/A:N",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "MEDIUM",
          "availabilityImpact": "NONE",
          "confidentialityImpact": "COMPLETE"
        },
        "acInsufInfo": false,
        "impactScore": 6.9,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 3.4,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
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    "cvssMetricV31": [
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          "scope": "UNCHANGED",
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          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N",
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  "published": "2021-06-23T16:15:07.957",
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "source": "nvd@nist.gov",
      "description": [
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          "value": "CWE-843"
        }
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  "descriptions": [
    {
      "lang": "en",
      "value": "In kernel/bpf/verifier.c in the Linux kernel before 5.12.13, a branch can be mispredicted (e.g., because of type confusion) and consequently an unprivileged BPF program can read arbitrary memory locations via a side-channel attack, aka CID-9183671af6db."
    },
    {
      "lang": "es",
      "value": "En el archivo kernel/bpf/verifier.c en el kernel de Linux versiones anteriores a 5.12.13, una rama puede ser mal predicha (por ejemplo, debido a la confusión de tipos) y, en consecuencia, un programa BPF no privilegiado puede leer ubicaciones de memoria arbitrarias por medio de un ataque de canal lateral, también conocido como CID-9183671af6db"
    }
  ],
  "lastModified": "2026-10-08T21:17:35.550",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
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              "vulnerable": true,
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              "versionEndExcluding": "5.12.13"
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}