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CVE-2020-27674

Status: ModifiedMedium (5.3)—

An issue was discovered in Xen through 4.14.x allowing x86 PV guest OS users to gain guest OS privileges by modifying kernel memory contents, because invalidation of TLB entries is mishandled during use of an INVLPG-like attack technique.

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 (3)

Debian — Debian LinuxFedoraproject — FedoraXEN — XEN

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2020-27674",
  "cveTags": [],
  "metrics": {
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          "vectorString": "AV:L/AC:L/Au:N/C:P/I:P/A:P",
          "authentication": "NONE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "PARTIAL"
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          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L",
          "integrityImpact": "LOW",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
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          "privilegesRequired": "LOW",
          "confidentialityImpact": "LOW"
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  "published": "2020-10-22T21:15:14.077",
  "references": [
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      "lang": "en",
      "value": "An issue was discovered in Xen through 4.14.x allowing x86 PV guest OS users to gain guest OS privileges by modifying kernel memory contents, because invalidation of TLB entries is mishandled during use of an INVLPG-like attack technique."
    },
    {
      "lang": "es",
      "value": "Se detectó un problema en Xen versiones hasta 4.14.x, permitiendo a usuarios de SO invitado de PV x86 alcanzar privilegios de SO invitado modificando el contenido de la memoria del kernel, porque una invalidación de las entradas TLB es manejada inapropiadamente durante el uso de una técnica de ataque similar a INVLPG"
    }
  ],
  "lastModified": "2026-06-17T03:09:28.790",
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}