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CVE-2025-66546
Good to know:
Date: December 5, 2025
Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.19, 5.5.6, and 6.0.1, the calendar app allowed blindly booking appointments with a squential ID without known the appointment token. This vulnerability is fixed in 4.7.19, 5.5.6, and 6.0.1.
Severity Score
Related Resources (6)
Severity Score
Weakness Type (CWE)
Authorization Bypass Through User-Controlled Key
CWE-639Top Fix
Upgrade Version
Upgrade to version https://github.com/nextcloud/calendar.git - v6.0.1;https://github.com/nextcloud/calendar.git - v5.5.6;https://github.com/nextcloud/calendar.git - v4.7.19
CVSS v3.1
| Base Score: |
|
|---|---|
| Attack Vector (AV): | LOCAL |
| Attack Complexity (AC): | LOW |
| Privileges Required (PR): | LOW |
| User Interaction (UI): | NONE |
| Scope (S): | UNCHANGED |
| Confidentiality (C): | LOW |
| Integrity (I): | NONE |
| Availability (A): | NONE |