CVE-2025-66546

published 2025-12-05

CVE-2025-66546: 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…

Priority P4 11 low 3.3 CVSS 3.1

AV L AC L PR L UI N S U C L I N A N

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.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
nextcloud	calendar	—	—
nextcloud	calendar	>= 4.0.0 < 4.7.19	4.7.19
nextcloud	calendar	>= 5.0.0 < 5.5.6	5.5.6
nextcloud	security-advisories	—	—
nextcloud	security-advisories	—	—
nextcloud	security-advisories	—	—

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CWE-639