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Status published
Low
CVE-2025-66546
Nextcloud Calendar app allowed booking appointments without the generated token
Vulnerability 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 Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
References
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Affected Vendor
nextcloud
View all reports →Affected Software
security-advisories
Vulnerable Versions:
>= 6.0.0-rc.1, < 6.0.1, >= 5.0.0-rc.1, < 5.5.6, >= 3.0.0-beta1, < 4.7.19
Timeline
Official Publish:
December 5th, 2025
Last Modified:
December 5th, 2025
Added to House:
July 22nd, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N