CVE-2025-66546

Nextcloud Calendar app allowed booking appointments without the generated token

State: Published
Severity: 3.3 Low
Published: Dec 5, 2025
Updated: Dec 5, 2025
Reserved: Dec 4, 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.

Scores

CVSS	Score	Vector	Source
3.1	3.3 Low	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N	GitHub_M

Weaknesses

CWE-639 Authorization Bypass Through User-Controlled Key

Affected Products

Product	Versions
security-advisoriesnextcloud	>= 6.0.0-rc.1, < 6.0.1Affected >= 5.0.0-rc.1, < 5.5.6Affected >= 3.0.0-beta1, < 4.7.19Affected

References

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