« Volver al listado

CVE-2025-66550

Estado: AnalizadaMedia (5.7)—

Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.17 and 5.2.4, when a malicious user creates a calendar event with a crafted attachment that links to a download link of a file on the same Nextcloud server, the file would be downloaded without the user confirming the action. This vulnerability is fixed in 4.7.17 and 5.2.4.

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).

Tecnologías afectadas (1)

Nextcloud — Calendar

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2025-66550",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2025-66550",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2025-12-05T18:37:20.458733Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "security-advisories@github.com",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 5.7,
          "attackVector": "NETWORK",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:N",
          "integrityImpact": "HIGH",
          "userInteraction": "REQUIRED",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 2.1
      }
    ]
  },
  "affected": [
    {
      "source": "security-advisories@github.com",
      "affectedData": [
        {
          "vendor": "nextcloud",
          "product": "security-advisories",
          "versions": [
            {
              "status": "affected",
              "version": ">= 5.0.0-rc.1, < 5.2.4"
            },
            {
              "status": "affected",
              "version": "< 4.7.17"
            }
          ]
        }
      ]
    }
  ],
  "published": "2025-12-05T17:16:05.500",
  "references": [
    {
      "url": "https://github.com/nextcloud/calendar/commit/63a6c398db01391eb9fd5297a0d4c3d6e614f769",
      "tags": [
        "Patch"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/nextcloud/calendar/pull/6971",
      "tags": [
        "Issue Tracking"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f29c-ppmv-8mcv",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://hackerone.com/reports/3112033",
      "tags": [
        "Issue Tracking",
        "Vendor Advisory"
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "security-advisories@github.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-241"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.17 and 5.2.4, when a malicious user creates a calendar event with a crafted attachment that links to a download link of a file on the same Nextcloud server, the file would be downloaded without the user confirming the action. This vulnerability is fixed in 4.7.17 and 5.2.4."
    }
  ],
  "lastModified": "2026-06-17T09:57:00.787",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:nextcloud:calendar:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "1B86471C-96D9-4152-BD53-8AC98B0C428D",
              "versionEndExcluding": "4.7.17",
              "versionStartIncluding": "4.0.0"
            },
            {
              "criteria": "cpe:2.3:a:nextcloud:calendar:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "833B51DE-8445-40F4-A4D4-E7B88F3C2B0C",
              "versionEndExcluding": "5.2.4",
              "versionStartIncluding": "5.0.0"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "security-advisories@github.com"
}