CVE-2016-9464
Nextcloud Server before 9.0.54 and 10.0.0 suffers from an improper authorization check on...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2016-9464- CVSS 3.0
- 4.3 Medium
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - CVSS 2.0
- 4.0 Medium
AV:N/AC:L/Au:S/C:N/I:P/A:N - Weakness
- CWE-285
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2016-9464- Weakness
- CWE-285
- Updated
- 2026-11-02
EUVDEUVD-2016-10270 No score
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.
- Record
EUVD-2016-10270- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-r69w-pvjm-xg3v
Nextcloud Server before 9.0.54 and 10.0.0 suffers from an improper authorization check on...
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.
- Record
GHSA-r69w-pvjm-xg3v- CVSS 3.0
- 4.3 Medium
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-285
- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2016-9464- CVSS 3.0
- 4.3 Medium
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2016-9464 is a medium vulnerability (CVSS 4.3) in Nextcloud Server, published March 28, 2017. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.62%, the 76th percentile. No source names a fixed version.
References
github.com/nextcloud/server/commit/7289cb5ec0b812992ab0dfb889744b94bc0994f0
securityfocus.com/bid/97287
nextcloud.com/security/advisory?id=nc-sa-2016-007
hackerone.com/reports/153905
nvd.nist.gov/vuln/detail/CVE-2016-9464