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CVE-2021-43056

Status: ModifiedMedium (5.5)—

An issue was discovered in the Linux kernel for powerpc before 5.14.15. It allows a malicious KVM guest to crash the host, when the host is running on Power8, due to an arch/powerpc/kvm/book3s_hv_rmhandlers.S implementation bug in the handling of the SRR1 register values.

CVSS

Exploitation probability (EPSS)

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).

Affected technologies (2)

Fedoraproject — FedoraLinux — Linux Kernel

CWEs

References

Raw JSON (NVD)

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  "id": "CVE-2021-43056",
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          "authentication": "NONE",
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      "value": "An issue was discovered in the Linux kernel for powerpc before 5.14.15. It allows a malicious KVM guest to crash the host, when the host is running on Power8, due to an arch/powerpc/kvm/book3s_hv_rmhandlers.S implementation bug in the handling of the SRR1 register values."
    },
    {
      "lang": "es",
      "value": "Se ha detectado un problema en el kernel de Linux para powerpc versiones anteriores a 5.14.15. Permite que un invitado KVM malicioso bloquee el host, cuando éste es ejecutado en Power8, debido a un error de implementación de arch/powerpc/kvm/book3s_hv_rmhandlers.S en el manejo de los valores del registro SRR1"
    }
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  "lastModified": "2026-06-17T04:10:27.040",
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