{"schemaVersion":3,"id":"CVE-2025-66550","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"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 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