Bug 2419466 (CVE-2025-66547)

Summary: CVE-2025-66547 nextcloud-server: Nextcloud Server users can modify tags on files that do not belong to them
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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An access control flaw has been discovered in Nextcloud. Non-privileged users can modify tags on files they should not have access to via bulk tagging.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2420190, 2420193, 2420195    
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Description OSIDB Bzimport 2025-12-05 17:02:41 UTC
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.