« Volver al listado

CVE-2026-55006

Estado: AnalizadaAlta (7.8)—

Insufficient granularity of access control in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally.

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).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

AV:L sin UI requiere acceso local → T1068. Autorizado escala privilegios en Exchange → gestión de cuentas (T1098.002) e impersonación (T1078.002). CWE-1220 (control de acceso insuficiente) permite manipulación de datos (T1565.001).

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Privileged Account ManagementMulti-factor AuthenticationUser TrainingUser Account ManagementThreat Intelligence ProgramRestrict File and Directory Permissions

Tecnologías afectadas (2)

Microsoft — Exchange ServerMicrosoft — Exchange Server Subscription Edition

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-55006",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-55006",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-07-13T00:00:00+00:00"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "secure@microsoft.com",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.8,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 1.8
      }
    ]
  },
  "affected": [
    {
      "source": "secure@microsoft.com",
      "affectedData": [
        {
          "vendor": "Microsoft",
          "product": "Microsoft Exchange Server 2016 Cumulative Update 23",
          "versions": [
            {
              "status": "affected",
              "version": "15.01.0.0",
              "lessThan": "15.01.2507.071",
              "versionType": "custom"
            }
          ],
          "platforms": [
            "x64-based Systems"
          ]
        },
        {
          "vendor": "Microsoft",
          "product": "Microsoft Exchange Server 2019 Cumulative Update 14",
          "versions": [
            {
              "status": "affected",
              "version": "15.02.0.0",
              "lessThan": "15.02.1544.043",
              "versionType": "custom"
            }
          ],
          "platforms": [
            "x64-based Systems"
          ]
        },
        {
          "vendor": "Microsoft",
          "product": "Microsoft Exchange Server 2019 Cumulative Update 15",
          "versions": [
            {
              "status": "affected",
              "version": "15.02.0.0",
              "lessThan": "15.02.1748.048",
              "versionType": "custom"
            }
          ],
          "platforms": [
            "x64-based Systems"
          ]
        },
        {
          "vendor": "Microsoft",
          "product": "Microsoft Exchange Server Subscription Edition RTM",
          "versions": [
            {
              "status": "affected",
              "version": "15.02.0.0",
              "lessThan": "15.02.2562.045",
              "versionType": "custom"
            }
          ],
          "platforms": [
            "x64-based Systems"
          ]
        }
      ]
    }
  ],
  "published": "2026-07-14T17:17:08.650",
  "references": [
    {
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55006",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "secure@microsoft.com"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "secure@microsoft.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-1220"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Insufficient granularity of access control in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally."
    }
  ],
  "lastModified": "2026-07-24T19:19:25.353",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "FF76AEDA-E574-40ED-B64F-8FDEF8CAC802"
            },
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_14:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "8C98993B-82A5-48CC-947F-896CEA0CDB7F"
            },
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_15:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7166BCE0-1D55-46B2-96B9-250AB4BB6291"
            },
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server_subscription_edition:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "83506387-99D4-4A70-8E86-50EE32A7A507",
              "versionEndExcluding": "15.02.2562.045"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "secure@microsoft.com"
}