CVE-2025-64055 is a severe vulnerability affecting the Fanvil x210 V2 IP phone model running firmware version 2.12.20. The flaw stems from an authentication bypass (CWE-287) that allows an unauthenticated attacker on the same local network segment to access administrative functions of the device. These functions include uploading arbitrary files, performing firmware updates, and rebooting the device, all without requiring any credentials or user interaction. The vulnerability is exploitable remotely within the local network, meaning that an attacker who gains access to the LAN can fully compromise the device. The CVSS v3.1 score of 9.8 indicates critical severity, with attack vector being network (local), no privileges required, no user interaction needed, and full impact on confidentiality, integrity, and availability. The lack of available patches or mitigations from the vendor at the time of publication increases the urgency for defensive measures. This vulnerability could be leveraged to disrupt telephony services, implant malicious firmware, or pivot into internal networks, posing significant risks to enterprise communications and security.

For European organizations, this vulnerability poses a critical risk to telephony infrastructure security and operational continuity. Compromise of Fanvil x210 V2 devices could lead to unauthorized interception or manipulation of voice communications, disruption of phone services through forced reboots or firmware tampering, and potential lateral movement within corporate networks. This is particularly concerning for sectors relying heavily on secure communications, such as government, finance, healthcare, and critical infrastructure. The ability to upload arbitrary files and update firmware without authentication could enable attackers to implant persistent backdoors or malware, undermining organizational confidentiality and integrity. The disruption of availability through device reboots or bricking could impact business operations and emergency communications. Given the local network attack vector, organizations with insufficient network segmentation or remote access to LAN segments are at heightened risk.

1. Immediately isolate Fanvil x210 V2 devices on dedicated VLANs with strict access controls to limit local network exposure. 2. Restrict administrative access to these devices to trusted management networks only, using firewall rules and network segmentation. 3. Monitor network traffic for unusual file uploads or firmware update attempts targeting these devices. 4. Disable any unnecessary services or protocols on the devices to reduce attack surface. 5. Engage with Fanvil or authorized vendors to obtain firmware updates or patches as soon as they become available. 6. Implement network access control (NAC) to prevent unauthorized devices from connecting to the LAN. 7. Conduct regular audits of device configurations and logs to detect signs of compromise. 8. Educate IT staff about the vulnerability and ensure incident response plans include scenarios involving telephony device compromise.