CVE-2025-3719 is an access control vulnerability classified under CWE-863 (Incorrect Authorization) found in the CLI functionality of Nozomi Networks Guardian. The flaw arises because a specific access restriction is not properly enforced for users with limited privileges. This allows an authenticated user, who should have restricted access, to issue administrative CLI commands. These commands can modify device configurations or affect the availability of the Guardian device, potentially disrupting its monitoring capabilities. The vulnerability is remotely exploitable over the network without requiring user interaction, and no elevated privileges beyond limited authentication are needed. The CVSS 4.0 base score is 7.2, reflecting high severity due to the ease of exploitation and the significant impact on confidentiality, integrity, and availability. No known exploits have been reported in the wild yet, but the vulnerability poses a serious risk to operational technology environments where Nozomi Guardian is deployed for cybersecurity monitoring and asset visibility. The lack of proper authorization enforcement could allow attackers to manipulate security monitoring configurations, disable alerts, or cause denial of service, undermining the security posture of critical infrastructure.

For European organizations, especially those operating in critical infrastructure sectors such as energy, manufacturing, transportation, and utilities, this vulnerability could have severe consequences. Unauthorized administrative access to Nozomi Guardian devices could lead to misconfiguration or disabling of security monitoring, resulting in undetected cyber intrusions or operational disruptions. This could compromise the integrity and availability of industrial control systems and critical assets, potentially causing safety hazards, financial losses, and regulatory non-compliance. The ability to alter device configurations remotely increases the risk of targeted attacks against European critical infrastructure, which is a high-value target in the current geopolitical climate. Additionally, disruption of Guardian’s monitoring capabilities could delay incident detection and response, amplifying the impact of subsequent attacks. Organizations relying on Nozomi Guardian for real-time visibility and threat detection must consider this vulnerability a significant risk to their operational security.

1. Immediately restrict CLI access to Nozomi Guardian devices to only trusted administrators and networks using network segmentation and access control lists. 2. Implement strict authentication and authorization policies, ensuring that users with limited privileges cannot access administrative commands. 3. Monitor CLI command logs for any unusual or unauthorized administrative activity to detect potential exploitation attempts early. 4. Apply vendor patches or updates as soon as they are released to address this vulnerability. 5. If patches are not yet available, consider deploying compensating controls such as disabling CLI access where feasible or using jump hosts with enhanced logging and monitoring. 6. Conduct regular audits of user privileges and access rights on Guardian devices to ensure least privilege principles are enforced. 7. Integrate Guardian device monitoring with centralized security information and event management (SIEM) systems for enhanced visibility. 8. Train operational technology security teams on this vulnerability and its potential impact to improve incident response readiness.