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CVE-2025-66546

Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
05/12/2025
Last modified:
09/12/2025

Description

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.

Impact

Vector 3.x
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N CVSS v3.1 Severity and Metrics:

Base Score: 3.30 LOW
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

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

Base Score 3.x
3.30
Severity 3.x
LOW

Vulnerable products and versions

CPE From Up to
cpe:2.3:a:nextcloud:calendar:*:*:*:*:*:*:*:* 4.0.0 (including) 4.7.19 (excluding)
cpe:2.3:a:nextcloud:calendar:*:*:*:*:*:*:*:* 5.0.0 (including) 5.5.6 (excluding)
cpe:2.3:a:nextcloud:calendar:6.0.0:-:*:*:*:*:*:*
cpe:2.3:a:nextcloud:calendar:6.0.0:rc1:*:*:*:*:*:*
cpe:2.3:a:nextcloud:calendar:6.0.0:rc2:*:*:*:*:*:*
cpe:2.3:a:nextcloud:calendar:6.0.0:rc3:*:*:*:*:*:*
cpe:2.3:a:nextcloud:calendar:6.0.0:rc4:*:*:*:*:*:*
cpe:2.3:a:nextcloud:calendar:6.0.0:rc5:*:*:*:*:*:*
cpe:2.3:a:nextcloud:calendar:6.0.0:rc6:*:*:*:*:*:*

To consult the complete list of CPE names with products and versions, see this page


References to Advisories, Solutions, and Tools