{"id":"CVE-2016-9464","url":"https://www.cyber-defence.io/tools/cve/CVE-2016-9464","generatedAt":"2026-10-28T21:52:43.129Z","title":"Nextcloud Server before 9.0.54 and 10.0.0 suffers from an improper authorization check on removing shares.","description":"Nextcloud Server before 9.0.54 and 10.0.0 suffers from an improper authorization check on removing shares. The Sharing Backend as implemented in Nextcloud does differentiate between shares to users and groups. In case of a received group share, users should be able to unshare the file to themselves but not to the whole group. The previous API implementation simply unshared the file to all users in the group.","published":"2017-03-28T02:59:01.000Z","lastModified":"2026-06-17T00:56:07.000Z","status":"Modified","sourceIdentifier":"support@hackerone.com","cvss":{"version":"3.0","score":4.3,"severity":"MEDIUM","vector":"CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N"},"cwe":["CWE-285"],"affected":["nextcloud/nextcloud server"],"epss":{"score":0.01624,"percentile":0.75999,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (1.62%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"http://www.securityfocus.com/bid/97287","tags":["Third Party Advisory","VDB Entry"],"source":"support@hackerone.com"},{"url":"https://github.com/nextcloud/server/commit/3387e5d00fcf6b2ea6b285a091e5743f545e7202","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"support@hackerone.com"},{"url":"https://github.com/nextcloud/server/commit/7289cb5ec0b812992ab0dfb889744b94bc0994f0","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"support@hackerone.com"},{"url":"https://github.com/nextcloud/server/commit/a5471b4a3e3f30e99e4de39c97c0c3b3c2f1618f","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"support@hackerone.com"},{"url":"https://github.com/nextcloud/server/commit/e2c4f4f9aa11bc92e8f2212cce73841b922187e8","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"support@hackerone.com"},{"url":"https://hackerone.com/reports/153905","tags":["Exploit","Third Party Advisory"],"source":"support@hackerone.com"},{"url":"https://nextcloud.com/security/advisory/?id=nc-sa-2016-007","tags":["Patch","Vendor Advisory"],"source":"support@hackerone.com"},{"url":"http://www.securityfocus.com/bid/97287","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/nextcloud/server/commit/3387e5d00fcf6b2ea6b285a091e5743f545e7202","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/nextcloud/server/commit/7289cb5ec0b812992ab0dfb889744b94bc0994f0","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/nextcloud/server/commit/a5471b4a3e3f30e99e4de39c97c0c3b3c2f1618f","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/nextcloud/server/commit/e2c4f4f9aa11bc92e8f2212cce73841b922187e8","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://hackerone.com/reports/153905","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://nextcloud.com/security/advisory/?id=nc-sa-2016-007","tags":["Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2016-9464","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}