CVE-2025-66546

LowCVSS 3.3/10Last modified Oct 18, 2026

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.

Metrics

CVSS 3.1 3.3/10CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Weakness enumeration

CWE-639

Affected software

No affected versions have been published.

Timeline

Published: Dec 5, 2025
Last modified: Oct 18, 2026
NVD status: Analyzed

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