OpenIM Server v3.8.3 contains a missing authorization vulnerability that allows any authenticated user to access admin-only management API endpoints by submitting POST requests with a regular user bearer token to /user/get_users, /user/get_all_users_uid, and /group/get_groups. Attackers can exploit the absent authverify.CheckAdmin() call in the GetPaginationUsers, GetAllUserID, and GetGroups handlers to enumerate all platform user accounts including userIDs, nicknames, and manager level flags, as well as all groups including private groups the user has never joined, exposing group names, owner IDs, and member counts.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
References 5
https://github.com/openimsdk/open-im-server
disclosure@vulncheck.com
https://github.com/openimsdk/open-im-server/commit/193870b2f938278b27a2d8347bd7…
disclosure@vulncheck.com
https://github.com/openimsdk/open-im-server/issues/3778
disclosure@vulncheck.com
https://github.com/openimsdk/open-im-server/pull/3781
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/openim-server-missing-authorization-on-use…
disclosure@vulncheck.com