CVE-2025-66547 MEDIUM

CVE-2025-66547: Nextcloud Server users can modify tags on files that do not belong to them

Vendor Nextcloud
Product security-advisories
Weakness CWE-639 · IDOR
Published December 5, 2025
Last update December 5, 2025
View on NVD All CVEs

CVSS base score

4.3/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality None
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

What the vulnerability does

01Description

Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Enterprise Server prior to 31.0.1, non-privileged users can modify tags on files they should not have access to via bulk tagging. This vulnerability is fixed in 31.0.1.

Key dates

02Disclosure timeline

December 5, 2025 CVE published
December 5, 2025 Record updated