CVE-2025-5416 is a vulnerability identified in the Red Hat Build of Keycloak, an open-source identity and access management solution widely used for single sign-on and authentication services. The vulnerability concerns the /admin/serverinfo endpoint, which, when accessed by an already authenticated user, can inadvertently disclose sensitive system environment information. This exposure does not allow for modification or disruption of services but leaks potentially sensitive data about the system configuration or environment variables that could aid an attacker in further reconnaissance or targeted attacks. The vulnerability requires the attacker to have valid credentials (high privileges) to access the endpoint, and no user interaction beyond authentication is necessary. The CVSS 3.1 base score is 2.7, reflecting a low severity primarily due to the limited impact (confidentiality only, no integrity or availability impact), the requirement for authenticated access, and the lack of known exploits in the wild. Although the affected versions are not explicitly listed, the vulnerability is specific to Red Hat’s distribution of Keycloak, which is commonly deployed in enterprise environments for identity management.

For European organizations, the impact of this vulnerability is generally low but should not be dismissed. Exposure of sensitive environment information can provide attackers with insights into system configurations, software versions, and potentially sensitive environment variables. This information can facilitate more sophisticated attacks such as privilege escalation, lateral movement, or targeted exploitation of other vulnerabilities. Organizations relying on Keycloak for authentication and identity management may face increased risk if attackers leverage this information to compromise accounts or infrastructure. While the vulnerability does not directly allow unauthorized access or service disruption, the indirect risk to confidentiality and the potential for chained attacks means that European entities, especially those in regulated sectors like finance, healthcare, and government, should address this issue promptly to maintain compliance and security posture.

To mitigate this vulnerability, European organizations should: 1) Apply any available patches or updates from Red Hat promptly once released, as the vulnerability is already published and likely to be addressed in upcoming releases. 2) Restrict access to the /admin/serverinfo endpoint strictly to the minimum necessary administrative users and consider additional network-level controls such as IP whitelisting or VPN access to limit exposure. 3) Implement robust monitoring and logging of access to administrative endpoints to detect any unusual or unauthorized access attempts. 4) Conduct regular audits of environment variables and system information exposure to ensure no sensitive data is unnecessarily exposed. 5) Employ the principle of least privilege for all Keycloak users, ensuring that only trusted and necessary accounts have administrative access. 6) Consider using Web Application Firewalls (WAFs) or API gateways to add an additional layer of filtering and control over administrative API endpoints.