CVE-2025-66547

MediumCVSS 4.3/10Last modified Oct 18, 2026

Description

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.

Metrics

CVSS 3.1 4.3/10CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Weakness enumeration

CWE-639

Affected software

Vendor	Product	Versions
nextcloud	security-advisories	< 31.0.1

References

https://github.com/nextcloud/security-advisories/security/advisories/GHSA-hq6c-r898-fgf2Patch, Vendor Advisory
https://github.com/nextcloud/server/commit/b44f1568f2dc97c746281d99e2342ad679e3d8a9Patch
https://github.com/nextcloud/server/issues/51247Issue Tracking
https://github.com/nextcloud/server/pull/51288Issue Tracking
https://hackerone.com/reports/3040887Permissions Required, Vendor Advisory

Timeline

Published: Dec 5, 2025
Last modified: Oct 18, 2026
NVD status: Analyzed

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