2017-04-05 20:00:00
hackerone
PUBLISHED
Nextcloud Server before 9.0.55 and 10.0.2 suffers from a permission increase on re-sharing via OCS API issue. A permission related issue within the OCS sharing API allowed an authenticated adversary to reshare shared files with an increasing permission set. This may allow an attacker to edit files in a share despite having only a read permission set. Note that this only affects folders and files that the adversary has at least read-only permissions for.