{"api_version":"1","generated_at":"2026-10-29T14:05:29+00:00","cve":"CVE-2025-66547","urls":{"html":"https://cve.report/CVE-2025-66547","api":"https://cve.report/api/cve/CVE-2025-66547.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2025-66547","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-66547"},"summary":{"title":"Nextcloud Server users can modify tags on files that do not belong to them","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.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2025-12-05 17:16:05","updated_at":"2026-10-18 14:10:00"},"problem_types":["CWE-639","CWE-639 CWE-639: Authorization Bypass Through User-Controlled Key"],"metrics":[{"version":"3.1","source":"security-advisories@github.com","type":"Secondary","score":"4.3","severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","baseScore":4.3,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"NONE"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"4.3","severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","data":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":4.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","version":"3.1"}}],"references":[{"url":"https://hackerone.com/reports/3040887","name":"https://hackerone.com/reports/3040887","refsource":"security-advisories@github.com","tags":["Permissions Required","Vendor Advisory"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/nextcloud/server/pull/51288","name":"https://github.com/nextcloud/server/pull/51288","refsource":"security-advisories@github.com","tags":["Issue Tracking"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/nextcloud/server/issues/51247","name":"https://github.com/nextcloud/server/issues/51247","refsource":"security-advisories@github.com","tags":["Issue Tracking"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/nextcloud/security-advisories/security/advisories/GHSA-hq6c-r898-fgf2","name":"https://github.com/nextcloud/security-advisories/security/advisories/GHSA-hq6c-r898-fgf2","refsource":"security-advisories@github.com","tags":["Patch","Vendor Advisory"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/nextcloud/server/commit/b44f1568f2dc97c746281d99e2342ad679e3d8a9","name":"https://github.com/nextcloud/server/commit/b44f1568f2dc97c746281d99e2342ad679e3d8a9","refsource":"security-advisories@github.com","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-66547","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-66547","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"nextcloud","product":"security-advisories","version":"affected < 31.0.1","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2025","cve_id":"66547","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"nextcloud","cpe5":"nextcloud_server","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"-","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2025","cve_id":"66547","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"nextcloud","cpe5":"nextcloud_server","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"enterprise","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"metrics":[{"other":{"content":{"id":"CVE-2025-66547","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","timestamp":"2025-12-05T18:20:11.023676Z","version":"2.0.3"},"type":"ssvc"}}],"providerMetadata":{"dateUpdated":"2025-12-05T18:20:43.503Z","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP"},"title":"CISA ADP Vulnrichment"}],"cna":{"affected":[{"product":"security-advisories","vendor":"nextcloud","versions":[{"status":"affected","version":"< 31.0.1"}]}],"descriptions":[{"lang":"en","value":"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":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":4.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-639","description":"CWE-639: Authorization Bypass Through User-Controlled Key","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2025-12-05T16:32:17.359Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"references":[{"name":"https://github.com/nextcloud/security-advisories/security/advisories/GHSA-hq6c-r898-fgf2","tags":["x_refsource_CONFIRM"],"url":"https://github.com/nextcloud/security-advisories/security/advisories/GHSA-hq6c-r898-fgf2"},{"name":"https://github.com/nextcloud/server/issues/51247","tags":["x_refsource_MISC"],"url":"https://github.com/nextcloud/server/issues/51247"},{"name":"https://github.com/nextcloud/server/pull/51288","tags":["x_refsource_MISC"],"url":"https://github.com/nextcloud/server/pull/51288"},{"name":"https://github.com/nextcloud/server/commit/b44f1568f2dc97c746281d99e2342ad679e3d8a9","tags":["x_refsource_MISC"],"url":"https://github.com/nextcloud/server/commit/b44f1568f2dc97c746281d99e2342ad679e3d8a9"},{"name":"https://hackerone.com/reports/3040887","tags":["x_refsource_MISC"],"url":"https://hackerone.com/reports/3040887"}],"source":{"advisory":"GHSA-hq6c-r898-fgf2","discovery":"UNKNOWN"},"title":"Nextcloud Server users can modify tags on files that do not belong to them"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2025-66547","datePublished":"2025-12-05T16:32:17.359Z","dateReserved":"2025-12-04T15:52:26.550Z","dateUpdated":"2025-12-05T18:20:43.503Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2025-12-05 17:16:05","lastModifiedDate":"2026-10-18 14:10:00","problem_types":["CWE-639","CWE-639 CWE-639: Authorization Bypass Through User-Controlled Key"],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","baseScore":4.3,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"NONE"},"exploitabilityScore":2.8,"impactScore":1.4}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2025-12-05T18:20:11.023676Z","id":"CVE-2025-66547","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:*","versionStartIncluding":"31.0.0","versionEndExcluding":"31.0.1","matchCriteriaId":"D8631F6B-EED4-4B47-84C3-7BC63464AC15"},{"vulnerable":true,"criteria":"cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:*","versionStartIncluding":"31.0.0","versionEndExcluding":"31.0.1","matchCriteriaId":"52B7D78F-BCCC-4178-BB21-AB9587D11386"}]}]}]},"legacy_mitre":{"record":{"CveYear":"2025","CveId":"66547","Ordinal":"1","Title":"Nextcloud Server users can modify tags on files that do not belo","CVE":"CVE-2025-66547","Year":"2025"},"notes":[{"CveYear":"2025","CveId":"66547","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"Nextcloud Server users can modify tags on files that do not belo"}]}}}