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CVE-2021-29155

Estado: ModificadaMedia (5.5)—💥 PoC

Se detectó un problema en el kernel de Linux versiones hasta 5.11.x. En el archivo kernel/bpf/verifier.c lleva a cabo especulaciones indeseables fuera de límites en la aritmética de punteros, conllevando a ataques de canal lateral que anulan las mitigaciones de Spectre y consiguen información confidencial de la memoria del kernel. Específicamente, para secuencias de operaciones aritméticas de puntero, la modificación de puntero llevada a cabo por la primera operación no se contabiliza correctamente al restringir operaciones posteriores

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 (3)

Debian — Debian LinuxFedoraproject — FedoraLinux — Linux Kernel

CWE

Referencias

JSON original (NVD)

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  "id": "CVE-2021-29155",
  "cveTags": [],
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          "vectorString": "AV:L/AC:L/Au:N/C:P/I:N/A:N",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "LOW",
          "availabilityImpact": "NONE",
          "confidentialityImpact": "PARTIAL"
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        "acInsufInfo": false,
        "impactScore": 2.9,
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        "obtainAllPrivilege": false,
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        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
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          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ]
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  "descriptions": [
    {
      "lang": "en",
      "value": "An issue was discovered in the Linux kernel through 5.11.x. kernel/bpf/verifier.c performs undesirable out-of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spectre mitigations and obtain sensitive information from kernel memory. Specifically, for sequences of pointer arithmetic operations, the pointer modification performed by the first operation is not correctly accounted for when restricting subsequent operations."
    },
    {
      "lang": "es",
      "value": "Se detectó un problema en el kernel de Linux versiones hasta 5.11.x. En el archivo kernel/bpf/verifier.c lleva a cabo especulaciones indeseables fuera de límites en la aritmética de punteros, conllevando a ataques de canal lateral que anulan las mitigaciones de Spectre y consiguen información confidencial de la memoria del kernel. Específicamente, para secuencias de operaciones aritméticas de puntero, la modificación de puntero llevada a cabo por la primera operación no se contabiliza correctamente al restringir operaciones posteriores"
    }
  ],
  "lastModified": "2026-06-17T03:47:22.490",
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}