« Volver al listado

CVE-2026-56164

Estado: AnalizadaCrítica (9.8)⚠ Explotación activa

Missing authentication for critical function in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.

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).

CISA KEV — explotada activamente

🎯 Técnicas ATT&CK

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

CVE crítico (CVSS 3.1 9.8) en SharePoint: autenticación faltante (CWE-306) en función crítica permite acceso remoto sin credenciales (AV:N/PR:N) → T1190. Impacto: escalada de privilegios y acceso de cuenta (T1078), con posible ejecución posterior (T1059) y manipulación de datos (T1565.001), confirma

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 ManagementApplication Developer GuidanceActive Directory ConfigurationVulnerability ScanningUser TrainingUser Account Management

Tecnologías afectadas (1)

Microsoft — Sharepoint Server

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-56164",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-56164",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "active"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-07-14T18:45:11.388695Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "secure@microsoft.com",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 5.3,
          "attackVector": "NETWORK",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
          "integrityImpact": "LOW",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 1.4,
        "exploitabilityScore": 3.9
      },
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 9.8,
          "attackVector": "NETWORK",
          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 3.9
      }
    ]
  },
  "affected": [
    {
      "source": "secure@microsoft.com",
      "affectedData": [
        {
          "vendor": "Microsoft",
          "product": "Microsoft SharePoint Enterprise Server 2016",
          "versions": [
            {
              "status": "affected",
              "version": "16.0.0",
              "lessThan": "16.0.5561.1001",
              "versionType": "custom"
            }
          ],
          "platforms": [
            "x64-based Systems"
          ]
        },
        {
          "vendor": "Microsoft",
          "product": "Microsoft SharePoint Server 2019",
          "versions": [
            {
              "status": "affected",
              "version": "16.0.0",
              "lessThan": "16.0.10417.20175",
              "versionType": "custom"
            }
          ],
          "platforms": [
            "x64-based Systems"
          ]
        },
        {
          "vendor": "Microsoft",
          "product": "Microsoft SharePoint Server Subscription Edition",
          "versions": [
            {
              "status": "affected",
              "version": "16.0.0",
              "lessThan": "16.0.19725.20434",
              "versionType": "custom"
            }
          ],
          "platforms": [
            "x64-based Systems"
          ]
        }
      ]
    }
  ],
  "published": "2026-07-14T17:17:09.907",
  "references": [
    {
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56164",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "secure@microsoft.com"
    },
    {
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-56164",
      "tags": [
        "US Government Resource"
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "secure@microsoft.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-306"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Missing authentication for critical function in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network."
    }
  ],
  "lastModified": "2026-07-14T21:10:41.693",
  "cisaActionDue": "2026-07-17",
  "cisaExploitAdd": "2026-07-14",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "5FA63EA8-B225-4E35-A6A3-DBDECF5AC4C8",
              "versionEndExcluding": "16.0.19725.20434"
            },
            {
              "criteria": "cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F815EF1D-7B60-47BE-9AC2-2548F99F10E4"
            },
            {
              "criteria": "cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "6122D014-5BF1-4AF4-8B4D-80205ED7785E"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "secure@microsoft.com",
  "cisaRequiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
  "cisaVulnerabilityName": "Microsoft SharePoint Server Missing Authentication for Critical Function Vulnerability"
}