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.
References (7)
Core 7
Core References
Issue Tracking, Patch, Third Party Advisory x_refsource_misc
https://github.com/nextcloud/server/commit/7289cb5ec0b812992ab0dfb889744b94bc0994f0
Issue Tracking, Patch, Third Party Advisory x_refsource_misc
https://github.com/nextcloud/server/commit/3387e5d00fcf6b2ea6b285a091e5743f545e7202
Issue Tracking, Patch, Third Party Advisory x_refsource_misc
https://github.com/nextcloud/server/commit/a5471b4a3e3f30e99e4de39c97c0c3b3c2f1618f
Issue Tracking, Patch, Third Party Advisory x_refsource_misc
https://github.com/nextcloud/server/commit/e2c4f4f9aa11bc92e8f2212cce73841b922187e8
Third Party Advisory, VDB Entry vdb-entry
x_refsource_bid
http://www.securityfocus.com/bid/97287
Patch, Vendor Advisory x_refsource_misc
https://nextcloud.com/security/advisory/?id=nc-sa-2016-007
Exploit, Third Party Advisory x_refsource_misc
https://hackerone.com/reports/153905
Scores
CVSS v3
4.3
EPSS
0.0029
EPSS Percentile
52.5%
Attack Vector
NETWORK
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Details
CWE
CWE-285
Status
published
Products (3)
n/a/Nextcloud Server Nextcloud Server before 9.0.54 and 10.0.0
Nextcloud Server Nextcloud Server before 9.0.54 and 10.0.0
nextcloud/nextcloud_server
10.0 rc1
nextcloud/nextcloud_server
< 9.0.54
Published
Mar 28, 2017
Tracked Since
Feb 18, 2026