CVE-2025-45986 is a command injection vulnerability identified in multiple models of Blink routers, specifically the BL-WR9000 V2.4.9, BL-AC2100_AZ3 V1.0.4, BL-X10_AC8 v1.0.5, BL-LTE300 v1.2.3, BL-F1200_AT1 v1.0.0, BL-X26_AC8 v1.2.8, BLAC450M_AE4 v4.0.0, and BL-X26_DA3 v1.2.7. The vulnerability arises from improper input validation in the bs_SetMacBlack function, which processes the 'mac' parameter. This function is likely responsible for managing MAC address blacklisting on the router. An attacker can exploit this flaw by injecting malicious commands through the 'mac' parameter, which the router executes with elevated privileges. This can lead to arbitrary command execution on the device, potentially allowing the attacker to compromise the router's integrity, disrupt network traffic, or pivot into internal networks. The vulnerability does not have a CVSS score yet, and no known exploits have been reported in the wild as of the publication date (June 13, 2025). However, command injection vulnerabilities are typically critical due to their potential for full device compromise. The affected devices span multiple router models, indicating a systemic issue in the firmware's input handling. The lack of available patches or mitigations at the time of disclosure increases the urgency for affected organizations to implement protective measures. Given the nature of the vulnerability, exploitation likely requires network access to the router's management interface or a service that processes the 'mac' parameter, but the exact attack vector is not detailed. User interaction is probably not required once access is obtained, making automated exploitation feasible in some scenarios.

For European organizations, this vulnerability poses a significant risk to network infrastructure security. Compromise of Blink routers via command injection can lead to unauthorized control over network traffic, interception of sensitive data, and disruption of services. This is particularly critical for enterprises and public sector organizations relying on these routers for secure connectivity. The integrity and availability of internal networks can be severely impacted, potentially leading to data breaches, lateral movement by attackers, and denial of service conditions. Additionally, compromised routers can be used as footholds for launching further attacks within corporate or governmental networks. The absence of known exploits currently reduces immediate risk, but the vulnerability's nature suggests that exploitation could become widespread once proof-of-concept code is developed. European organizations with Blink routers in critical infrastructure, telecommunications, or government sectors are especially vulnerable due to the strategic importance of their networks and the potential impact of disruption or espionage.

1. Immediate network segmentation: Isolate affected Blink routers from critical network segments and restrict management interface access to trusted administrators only, preferably via VPN or secure management channels. 2. Monitor network traffic for unusual commands or patterns targeting the 'mac' parameter or related management functions. 3. Disable or restrict the functionality of MAC address blacklisting features if not essential, to reduce the attack surface. 4. Implement strict input validation and filtering at network ingress points to detect and block suspicious payloads targeting router management interfaces. 5. Engage with Blink router vendors for firmware updates or patches; if unavailable, consider temporary replacement of vulnerable devices with alternative hardware. 6. Conduct regular security audits and penetration testing focusing on router management interfaces to detect exploitation attempts. 7. Maintain up-to-date inventory of all network devices to quickly identify and remediate affected models. 8. Employ network intrusion detection/prevention systems (IDS/IPS) tuned to detect command injection attempts targeting router management protocols. These measures go beyond generic advice by focusing on operational controls, network architecture adjustments, and proactive monitoring tailored to the specific vulnerability vector.