« Volver al listado

CVE-2021-3929

Estado: ModificadaAlta (8.2)—💥 PoC

A DMA reentrancy issue was found in the NVM Express Controller (NVME) emulation in QEMU. This CVE is similar to CVE-2021-3750 and, just like it, when the reentrancy write triggers the reset function nvme_ctrl_reset(), data structs will be freed leading to a use-after-free issue. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition or, potentially, executing arbitrary code within the context of the QEMU process on the host.

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)

Fedoraproject — FedoraQemu — Qemu

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2021-3929",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "CHANGED",
          "version": "3.1",
          "baseScore": 8.2,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "HIGH",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 6,
        "exploitabilityScore": 1.5
      }
    ]
  },
  "affected": [
    {
      "source": "secalert@redhat.com",
      "affectedData": [
        {
          "vendor": "n/a",
          "product": "QEMU",
          "versions": [
            {
              "status": "affected",
              "version": "Fixed in qemu-kvm 7.0.0-rc0"
            }
          ]
        }
      ]
    }
  ],
  "published": "2022-08-25T20:15:09.417",
  "references": [
    {
      "url": "https://access.redhat.com/security/cve/CVE-2021-3929",
      "tags": [
        "Third Party Advisory"
      ],
      "source": "secalert@redhat.com"
    },
    {
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2020298",
      "tags": [
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "source": "secalert@redhat.com"
    },
    {
      "url": "https://gitlab.com/qemu-project/qemu/-/commit/736b01642d85be832385",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "source": "secalert@redhat.com"
    },
    {
      "url": "https://gitlab.com/qemu-project/qemu/-/issues/556",
      "tags": [
        "Issue Tracking",
        "Third Party Advisory"
      ],
      "source": "secalert@redhat.com"
    },
    {
      "url": "https://gitlab.com/qemu-project/qemu/-/issues/782",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "source": "secalert@redhat.com"
    },
    {
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XHNN7QJCEQH7AQG5AQP2GEFAQE6K635I/",
      "source": "secalert@redhat.com"
    },
    {
      "url": "https://access.redhat.com/security/cve/CVE-2021-3929",
      "tags": [
        "Third Party Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2020298",
      "tags": [
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://gitlab.com/qemu-project/qemu/-/commit/736b01642d85be832385",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://gitlab.com/qemu-project/qemu/-/issues/556",
      "tags": [
        "Issue Tracking",
        "Third Party Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://gitlab.com/qemu-project/qemu/-/issues/782",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XHNN7QJCEQH7AQG5AQP2GEFAQE6K635I/",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://security.netapp.com/advisory/ntap-20250228-0010/",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "secalert@redhat.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    },
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "A DMA reentrancy issue was found in the NVM Express Controller (NVME) emulation in QEMU. This CVE is similar to CVE-2021-3750 and, just like it, when the reentrancy write triggers the reset function nvme_ctrl_reset(), data structs will be freed leading to a use-after-free issue. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition or, potentially, executing arbitrary code within the context of the QEMU process on the host."
    },
    {
      "lang": "es",
      "value": "Se ha encontrado un problema de reentrada DMA en la emulación del controlador NVM Express (NVME) en QEMU. Este CVE es similar al CVE-2021-3750 y, al igual que éste, cuando la escritura de reentrada desencadena la función de reinicio nvme_ctrl_reset(), los structs de datos serán liberados conllevando a un problema de uso de memoria previamente liberada. Un huésped malicioso podría usar este fallo para bloquear el proceso QEMU en el host, resultando en una condición de denegación de servicio o, potencialmente, una ejecución de código arbitrario dentro del contexto del proceso QEMU en el host."
    }
  ],
  "lastModified": "2026-06-17T04:06:00.403",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "9D977C76-0598-40D0-BF46-0D987515764C",
              "versionEndExcluding": "7.0.0"
            }
          ],
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "80E516C0-98A4-4ADE-B69F-66A772E2BAAA"
            },
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "5C675112-476C-4D7C-BCB9-A2FB2D0BC9FD"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "secalert@redhat.com"
}