CVE-2025-43732 is a medium-severity vulnerability affecting multiple versions of Liferay Portal and Liferay DXP, specifically versions 7.4.0 through 7.4.3.132 and various 2024 and 2025 quarterly releases. The vulnerability is classified under CWE-639, which corresponds to Authorization Bypass Through User-Controlled Key. The issue arises from an Insecure Direct Object Reference (IDOR) in the groupId parameter of the RolesSelectorPortlet (_com_liferay_roles_selector_web_portlet_RolesSelectorPortlet_groupId). This parameter is intended to restrict access to user lists within an organization. However, when an organization administrator modifies the groupId parameter value, they can bypass authorization controls and gain unauthorized access to user lists belonging to other organizations. This flaw indicates insufficient validation of the groupId parameter against the administrator's actual permissions, allowing privilege escalation within the portal environment. The vulnerability does not require network-level authentication (AV:N), but it does require a privileged role (PR:H) and user interaction (UI:P), such as an administrator manually modifying the parameter. The impact on confidentiality is low, as it exposes user lists but not necessarily sensitive data beyond that. Integrity and availability impacts are negligible. No known exploits are currently reported in the wild, and no official patches have been linked yet. The vulnerability affects a widely used enterprise portal platform that is often deployed in corporate intranets and extranets for content management and collaboration.

For European organizations, this vulnerability poses a risk primarily to the confidentiality of user information within Liferay Portal deployments. Unauthorized access to user lists across organizational boundaries could lead to privacy violations, data leakage, and potential misuse of user data for social engineering or further attacks. Organizations relying on Liferay Portal for internal collaboration or customer portals may face compliance risks under GDPR if personal data is exposed without proper authorization. Although the vulnerability requires an organization administrator role to exploit, insider threats or compromised administrator accounts could leverage this flaw to escalate access improperly. The impact on operational integrity and availability is minimal, but the breach of access controls undermines trust in the portal's security. Given Liferay's popularity among European enterprises, especially in sectors like government, education, and large corporations, the vulnerability could affect sensitive environments if not addressed promptly.

1. Immediate mitigation should include restricting administrator privileges to only trusted personnel and monitoring administrative activities for unusual parameter modifications. 2. Implement strict input validation and authorization checks on the groupId parameter within the RolesSelectorPortlet to ensure administrators can only access user lists within their own organizations. 3. Apply any forthcoming official patches from Liferay as soon as they are released. 4. Use web application firewalls (WAFs) to detect and block suspicious requests that attempt to manipulate the groupId parameter. 5. Conduct regular audits of user access logs to identify unauthorized access attempts. 6. Consider segmenting Liferay Portal instances by organization to reduce cross-organization exposure. 7. Educate administrators about the risks of parameter tampering and enforce secure administration practices. 8. If possible, implement multi-factor authentication (MFA) for administrator accounts to reduce the risk of compromised credentials being used to exploit this vulnerability.