CVE-2026-82633 in Dolibarr
Summary
by MITRE • 08/30/2026
Dolibarr versions 10.0.0 before 24.0.0 fail to perform per-object authorization checks in the Users::getGroups REST API endpoint, allowing authenticated users to retrieve group memberships of other users. Attackers can call GET /users/{id}/groups with arbitrary user identifiers to access group names, entity associations, and private notes across tenant boundaries.
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Analysis
by VulDB Data Team • 08/30/2026
The vulnerability identified in Dolibarr versions 10.0.0 through 24.0.0 represents a critical failure in the application's authorization logic within its REST API implementation. Specifically, the Users::getGroups endpoint lacks proper per-object access control checks. In secure software architecture, any operation that retrieves sensitive data associated with a specific resource must verify that the requesting user has explicit permission to view or modify that particular instance of the resource. However, in this flawed implementation, the server-side validation mechanism fails to cross-reference the authenticated session's identity and permissions against the target user identifier provided in the request payload. This oversight effectively transforms what should be an object-specific restriction into a function-level check, where authentication is verified but authorization for specific data objects is ignored.
This technical flaw allows any authenticated user to exploit the API by supplying arbitrary user identifiers in the GET /users/{id}/groups endpoint parameter. By manipulating this identifier, an attacker can bypass intended access boundaries and retrieve group membership details belonging to other users within the system. The exposed information includes not only standard group names but also sensitive entity associations and private notes linked to those groups. In multi-tenant deployments or environments with strict role-based access control policies, such as financial institutions or healthcare providers using Dolibarr for enterprise resource planning, this exposure can lead to significant privacy violations and operational security risks. The ability to map out the organizational structure through group memberships provides attackers with valuable intelligence that facilitates further lateral movement within the network.
From a classification perspective, this vulnerability aligns directly with CWE-284, which describes Improper Access Control, specifically falling under the sub-category of insufficient authorization checks for specific objects. Furthermore, in the context of the MITRE ATT&CK framework, this behavior is indicative of T1078, Valid Accounts, as it relies on legitimate credentials to access unauthorized resources, and potentially T1069, Permission Groups Discovery, which involves gathering information about group memberships to understand the environment's structure. The exploitation does not require complex payload construction or buffer overflow techniques; rather, it exploits a logical error in the API handler that trusts user-supplied input without adequate server-side validation against the current session's privileges.
The operational impact of this vulnerability extends beyond simple data leakage. By understanding which users belong to specific groups and entities, an attacker can identify high-value targets or administrative accounts within the organization. This intelligence is often a precursor to more severe attacks such as privilege escalation or targeted phishing campaigns. Additionally, in multi-tenant SaaS environments where different organizations share the same instance of Dolibarr, this flaw could potentially allow one tenant's users to access data belonging to another tenant if group structures are not strictly isolated at the database level by entity IDs alone. This undermines the fundamental security principle of isolation between distinct organizational units sharing a platform.
To mitigate this vulnerability, administrators must upgrade immediately to version 24.0.1 or later, where the per-object authorization checks have been implemented and validated in the REST API endpoints. For organizations unable to patch immediately due to operational constraints, temporary mitigations should focus on restricting access to the /users/ endpoint via web application firewalls by validating that the user ID parameter matches the authenticated session's own identifier. Additionally, implementing strict input validation at the proxy level can help block requests where the target resource does not align with the requester's permissions. Regular security audits of API endpoints are recommended to ensure that future updates do not reintroduce similar logical flaws in access control mechanisms.