{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-66550",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2025-12-04T15:57:22.034Z",
        "datePublished": "2025-12-05T16:56:44.680Z",
        "dateUpdated": "2025-12-05T18:41:24.347Z"
    },
    "containers": {
        "cna": {
            "title": "Nextcloud Calendar attachments of local files are offered to downloaded",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-241",
                            "lang": "en",
                            "description": "CWE-241: Improper Handling of Unexpected Data Type",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "NONE",
                        "baseScore": 5.7,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "HIGH",
                        "privilegesRequired": "LOW",
                        "scope": "UNCHANGED",
                        "userInteraction": "REQUIRED",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:N",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f29c-ppmv-8mcv",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f29c-ppmv-8mcv"
                },
                {
                    "name": "https://github.com/nextcloud/calendar/pull/6971",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/nextcloud/calendar/pull/6971"
                },
                {
                    "name": "https://github.com/nextcloud/calendar/commit/63a6c398db01391eb9fd5297a0d4c3d6e614f769",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/nextcloud/calendar/commit/63a6c398db01391eb9fd5297a0d4c3d6e614f769"
                },
                {
                    "name": "https://hackerone.com/reports/3112033",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://hackerone.com/reports/3112033"
                }
            ],
            "affected": [
                {
                    "vendor": "nextcloud",
                    "product": "security-advisories",
                    "versions": [
                        {
                            "version": ">= 5.0.0-rc.1, < 5.2.4",
                            "status": "affected"
                        },
                        {
                            "version": "< 4.7.17",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2025-12-05T16:56:44.680Z"
            },
            "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."
                }
            ],
            "source": {
                "advisory": "GHSA-f29c-ppmv-8mcv",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2025-12-05T18:37:20.458733Z",
                                "id": "CVE-2025-66550",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2025-12-05T18:41:24.347Z"
                }
            }
        ]
    }
}