CVE-2025-62864 is a critical vulnerability identified in Ampere AmpereOne AC03, AC04, and M series devices running UEFI firmware versions prior to 3.5.9.3, 4.4.5.2, and 5.4.5.1 respectively. The vulnerability stems from an out-of-bounds write condition triggered by an incorrectly formed Secure Monitor Call (SMC) to the UEFI-MM MMCommunicate service, which operates within the UEFI Management Mode (MM) Secure Partition context. This context is a highly privileged execution environment responsible for secure firmware operations. The out-of-bounds write (CWE-787) can corrupt memory, potentially allowing an attacker to execute arbitrary code with elevated privileges, leading to full compromise of the firmware layer. The vulnerability is remotely exploitable over the network without requiring any authentication or user interaction, as indicated by the CVSS vector (AV:N/AC:L/PR:N/UI:N). Exploitation could result in complete loss of confidentiality, integrity, and availability of the affected systems. Although no known exploits are currently reported in the wild, the critical CVSS score of 9.8 underscores the urgency of addressing this flaw. The affected devices are typically deployed in data centers and enterprise environments, where firmware integrity is paramount. The lack of available patches at the time of disclosure necessitates immediate risk mitigation through network controls and monitoring until official updates are released.

The impact of CVE-2025-62864 on European organizations is significant due to the critical nature of the vulnerability and the privileged execution context it affects. Successful exploitation can lead to complete firmware compromise, allowing attackers to bypass operating system security controls, persist undetected, and potentially manipulate or disrupt critical infrastructure systems. This poses a high risk to data confidentiality, system integrity, and availability, especially in sectors relying on AmpereOne devices for server and network infrastructure. European enterprises and government agencies using these devices could face severe operational disruptions, data breaches, and long-term security ramifications. The vulnerability's network exploitability without authentication increases the attack surface, making it a prime target for sophisticated threat actors. The absence of patches at disclosure heightens the risk window, necessitating immediate defensive measures. Additionally, the potential for firmware-level compromise complicates incident response and recovery efforts, as reimaging or replacing hardware may be required to fully remediate the threat.

1. Monitor vendor communications closely and apply firmware updates for AmpereOne AC03, AC04, and M devices as soon as patches become available to remediate the vulnerability. 2. Implement network-level filtering to restrict or block malformed SMC calls to the UEFI-MM MMCommunicate service, limiting exposure to remote exploitation. 3. Employ intrusion detection and prevention systems (IDPS) capable of identifying anomalous UEFI-related traffic or behavior indicative of exploitation attempts. 4. Conduct firmware integrity checks and enable secure boot features to detect unauthorized modifications to the UEFI firmware. 5. Isolate critical infrastructure systems using these devices within segmented network zones to reduce attack surface and lateral movement opportunities. 6. Develop and test incident response plans that include firmware compromise scenarios to ensure rapid containment and recovery. 7. Engage with hardware vendors for guidance on interim mitigations and best practices until official patches are deployed. 8. Maintain up-to-date asset inventories to identify all affected devices and prioritize remediation efforts accordingly.