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CVE-2025-66550
Good to know:
Date: December 5, 2025
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.
Severity Score
Related Resources (6)
Severity Score
Weakness Type (CWE)
Improper Handling of Unexpected Data Type
CWE-241Top Fix
Upgrade Version
Upgrade to version https://github.com/nextcloud/calendar.git - v4.7.17;https://github.com/nextcloud/calendar.git - v5.2.4
CVSS v3.1
| Base Score: |
|
|---|---|
| Attack Vector (AV): | NETWORK |
| Attack Complexity (AC): | LOW |
| Privileges Required (PR): | LOW |
| User Interaction (UI): | REQUIRED |
| Scope (S): | UNCHANGED |
| Confidentiality (C): | NONE |
| Integrity (I): | HIGH |
| Availability (A): | NONE |