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CVE-2021-4093

Estado: ModificadaAlta (8.8)—

A flaw was found in the KVM's AMD code for supporting the Secure Encrypted Virtualization-Encrypted State (SEV-ES). A KVM guest using SEV-ES can trigger out-of-bounds reads and writes in the host kernel via a malicious VMGEXIT for a string I/O instruction (for example, outs or ins) using the exit reason SVM_EXIT_IOIO. This issue results in a crash of the entire system or a potential guest-to-host escape scenario.

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).

Tecnologías afectadas (4)

Canonical — Ubuntu LinuxFedoraproject — FedoraLinux — Linux KernelRedhat — Enterprise Linux

CWE

Referencias

JSON original (NVD)

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  "id": "CVE-2021-4093",
  "cveTags": [],
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          "vectorString": "AV:L/AC:L/Au:N/C:C/I:C/A:C",
          "authentication": "NONE",
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          "availabilityImpact": "COMPLETE",
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          "value": "CWE-787"
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      "value": "A flaw was found in the KVM's AMD code for supporting the Secure Encrypted Virtualization-Encrypted State (SEV-ES). A KVM guest using SEV-ES can trigger out-of-bounds reads and writes in the host kernel via a malicious VMGEXIT for a string I/O instruction (for example, outs or ins) using the exit reason SVM_EXIT_IOIO. This issue results in a crash of the entire system or a potential guest-to-host escape scenario."
    },
    {
      "lang": "es",
      "value": "Se ha encontrado un fallo en el código de AMD de KVM para soportar la Virtualización Segura Encriptada-Estado Encriptado (SEV-ES). Un huésped de KVM que use SEV-ES puede desencadenar lecturas y escrituras fuera de límites en el núcleo anfitrión por medio de un VMGEXIT malicioso para una instrucción de E/S de cadena (por ejemplo, outs o ins) usando el motivo de salida SVM_EXIT_IOIO. Este problema resulta en un bloqueo de todo el sistema o en un potencial escenario de escape del huésped al host"
    }
  ],
  "lastModified": "2026-06-17T04:19:01.410",
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