CVE-2025-63288 identifies a denial of service vulnerability in Open5GS version 2.7.6, specifically targeting the Access and Mobility Management Function (AMF). The AMF is a critical component of the 5G core network responsible for managing mobility and access control. The vulnerability arises when the AMF processes an abnormal NGSetupRequest message, which is part of the NG interface setup procedure between the 5G core and the next-generation NodeB (gNB). The malformed NGSetupRequest causes the AMF process to crash, resulting in a denial of service that disrupts the availability of the 5G core network services. The vulnerability is classified under CWE-400 (Uncontrolled Resource Consumption), indicating that the abnormal message triggers resource exhaustion or improper handling leading to a crash. The CVSS 3.1 base score is 7.5, reflecting a high severity due to the network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), and no user interaction needed (UI:N). The impact is limited to availability (A:H) with no confidentiality or integrity loss. No patches are currently linked, and no known exploits have been reported in the wild, but the potential for disruption is significant given the critical role of AMF in 5G networks.

The primary impact of this vulnerability is a denial of service condition affecting the availability of the 5G core network's AMF component. For European organizations, particularly telecom operators and mobile network providers deploying Open5GS or similar 5G core solutions, exploitation could lead to service outages, degraded network performance, and loss of connectivity for end-users. This disruption could affect critical communications, emergency services, and enterprise connectivity relying on 5G infrastructure. The lack of confidentiality or integrity impact limits data breach risks, but the availability impact on essential telecommunications infrastructure is severe. Additionally, prolonged or repeated exploitation could strain network resources and complicate incident response efforts. The absence of known exploits currently provides a window for proactive mitigation, but the ease of exploitation and network accessibility of the AMF make timely action imperative.

1. Monitor vendor communications and apply official patches or updates for Open5GS as soon as they become available to address CVE-2025-63288. 2. Implement network-level filtering and anomaly detection to identify and block malformed NGSetupRequest messages before they reach the AMF. 3. Employ rate limiting on NG interface traffic to reduce the risk of resource exhaustion from abnormal requests. 4. Enhance logging and monitoring on the AMF to detect crashes or abnormal behavior promptly, enabling rapid incident response. 5. Consider deploying redundant AMF instances and failover mechanisms to maintain service continuity in case of a crash. 6. Conduct regular security assessments and penetration testing on 5G core components to identify and remediate similar vulnerabilities proactively. 7. Collaborate with telecom equipment vendors and security communities to share threat intelligence and mitigation strategies specific to 5G core vulnerabilities.