CVE-2022-39067 is a buffer overflow vulnerability identified in the ZTE MF286R device, specifically affecting the Nordic_MF286R_B06 firmware version. The vulnerability arises due to insufficient input validation on parameters related to the Wi-Fi interface. An authenticated attacker, meaning one who has valid access credentials to the device, can exploit this flaw by sending specially crafted input to the Wi-Fi interface parameters. This triggers a buffer overflow condition (classified under CWE-120), which can lead to a denial of service (DoS) state by crashing or destabilizing the device. The vulnerability does not impact confidentiality or integrity directly, as it does not allow data leakage or unauthorized modification, but it severely affects availability by rendering the device inoperable. The CVSS v3.1 base score is 6.5, indicating a medium severity level. The attack vector is network-based (AV:N), requiring low attack complexity (AC:L), but it does require privileges (PR:L) since the attacker must be authenticated. No user interaction is needed (UI:N), and the scope is unchanged (S:U). There are no known exploits in the wild, and no patches have been linked or published yet. The MF286R is a 4G/5G wireless router commonly used in various regions, including Europe, for broadband connectivity, especially in areas lacking wired infrastructure. The vulnerability could be leveraged to disrupt network connectivity for users relying on these devices.

For European organizations, the primary impact of this vulnerability is the potential disruption of network availability. Organizations using the ZTE MF286R as part of their network infrastructure, particularly in remote or mobile broadband scenarios, could experience service outages if an attacker exploits this flaw. This could affect business continuity, especially for critical operations relying on stable internet access. While the vulnerability does not compromise data confidentiality or integrity, the denial of service could interrupt communications, remote work, and access to cloud services. Given the requirement for authentication, the threat is more relevant to internal or semi-trusted environments where attackers have some level of access, such as disgruntled employees or compromised internal accounts. The lack of known exploits reduces immediate risk, but the absence of patches means the vulnerability remains a persistent threat. Additionally, disruption of connectivity in sectors like healthcare, manufacturing, or public services could have cascading effects on operational efficiency and safety.

1. Restrict access to the device management interfaces to trusted personnel only, enforcing strong authentication and network segmentation to limit exposure. 2. Monitor device logs and network traffic for unusual activity or repeated failed attempts to modify Wi-Fi parameters, which could indicate exploitation attempts. 3. Implement network-level protections such as firewall rules to restrict access to the device’s management ports from untrusted networks. 4. Where possible, replace or upgrade affected devices to models or firmware versions not vulnerable to this issue once patches become available. 5. Employ network redundancy and failover mechanisms to minimize impact if a device becomes unavailable due to exploitation. 6. Conduct regular security audits and vulnerability assessments on network infrastructure devices to identify and remediate similar issues proactively. 7. Educate internal users about the risks of credential compromise and enforce strong password policies to reduce the risk of unauthorized authenticated access.