CVE-2025-66547

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.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-hq6c-r898-fgf2	Patch Vendor Advisory
https://github.com/nextcloud/server/commit/b44f1568f2dc97c746281d99e2342ad679e3d8a9	Patch
https://github.com/nextcloud/server/issues/51247	Issue Tracking
https://github.com/nextcloud/server/pull/51288	Issue Tracking
https://hackerone.com/reports/3040887	Permissions Required Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:nextcloud:nextcloud_server:::::-:::*
	cpe:2.3:a:nextcloud:nextcloud_server:::::enterprise:::*

History

No history.

Information

Published : 2025-12-05 17:16

Updated : 2025-12-09 16:31

NVD link : CVE-2025-66547

Mitre link : CVE-2025-66547

CVE.ORG link : CVE-2025-66547

JSON object : View

Products Affected

nextcloud

nextcloud_server

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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