Authorization bypass through user-controlled key in Nextcloud Calendar - CVE-2025-66546
Published: December 8, 2025
Vulnerability identifier: #VU119262
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2025-66546
CWE-ID: CWE-639
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Nextcloud
Affected software:
Nextcloud Calendar
Nextcloud Calendar
Detailed vulnerability description
The vulnerability allows a local user to compromise the target system.
The vulnerability exists due to the affected application allows booking appointments without the generated token. A local user can gain access to sensitive information on the system.
How to mitigate CVE-2025-66546
Install updates from vendor's website.