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 ID without known the appointment token. This vulnerability is fixed in 4.7.19, 5.5.6, and 6.0.1.

CVSS v3 3.3 LOW

3.3^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.8 / Impact : 1.4

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/nextcloud/calendar/commit/f41650c3681fc4a4130eb883f5c0899c011326b3	Patch
https://github.com/nextcloud/calendar/pull/7537	Issue Tracking
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-7x2j-2674-fj95	Patch Vendor Advisory
https://hackerone.com/reports/3275810	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:nextcloud:calendar::::::::
	cpe:2.3:a:nextcloud:calendar::::::::
	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::::::

History

No history.

Information

Published : 2025-12-05 17:16

Updated : 2025-12-09 16:36

NVD link : CVE-2025-66546

Mitre link : CVE-2025-66546

CVE.ORG link : CVE-2025-66546

JSON object : View

Products Affected

nextcloud

calendar

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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