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.
Affected products
nextcloud: nextcloud server
References5
- github.com/nextcloud/security-advisories/security/advisories/GH… PatchVendor Advisory
- hackerone.com/reports/3040887 Permissions RequiredVendor Advisory
- github.com/nextcloud/server/commit/b44f1568f2dc97c746281d99e234… Patch
- github.com/nextcloud/server/issues/51247 Issue Tracking
- github.com/nextcloud/server/pull/51288 Issue Tracking
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 23 · as of 11 November 2026
- CWE
- CWE-639
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