CVE-2026-1506 is an OS command injection vulnerability identified in the D-Link DIR-615 router firmware version 4.10, specifically within the MAC Filter Configuration functionality implemented in the /adv_mac_filter.php file. The vulnerability is triggered by manipulation of the 'mac' argument, which is not properly sanitized before being passed to an operating system command. This flaw allows a remote attacker to execute arbitrary OS commands on the device without requiring authentication or user interaction, as the attack vector is network accessible. The vulnerability's CVSS 4.0 score is 8.6 (high), reflecting its ease of exploitation (network attack vector, low attack complexity, no privileges or user interaction needed) and its severe impact on confidentiality, integrity, and availability. The affected product, D-Link DIR-615 version 4.10, is no longer supported by the vendor, meaning no official patches or updates are available. The public disclosure of exploit code increases the likelihood of exploitation by threat actors. Successful exploitation could lead to full device compromise, enabling attackers to control network traffic, intercept sensitive data, or launch further attacks within the network. Given the widespread use of D-Link routers in small to medium enterprises and home environments, this vulnerability poses a significant risk, especially where legacy devices remain in operation.

For European organizations, the impact of CVE-2026-1506 can be substantial. Compromise of the DIR-615 router can lead to unauthorized access to internal networks, interception or manipulation of sensitive communications, and disruption of network availability. This is particularly critical for organizations in sectors such as finance, healthcare, and critical infrastructure that rely on secure and stable network connectivity. The lack of vendor support means no official patches are available, increasing the risk of persistent exploitation. Additionally, the public availability of exploit code lowers the barrier for attackers, including cybercriminals and nation-state actors, to leverage this vulnerability. Organizations using these legacy devices may face regulatory compliance issues under GDPR if data breaches occur due to this vulnerability. The risk is amplified in environments where network segmentation is weak or where these routers serve as primary gateways to sensitive systems.

Given the absence of vendor patches, European organizations should prioritize the following mitigations: 1) Immediate identification and inventory of all D-Link DIR-615 devices running firmware version 4.10 within their networks. 2) Segmentation or isolation of these devices from critical network segments to limit potential lateral movement. 3) Replacement of affected routers with currently supported models that receive security updates. 4) Deployment of network intrusion detection systems (NIDS) and continuous monitoring to detect anomalous command injection attempts or unusual traffic patterns targeting the MAC filter configuration interface. 5) Implementation of strict access controls and firewall rules to restrict remote access to router management interfaces. 6) Educating IT staff about the risks associated with legacy hardware and the importance of timely hardware lifecycle management. 7) Where replacement is not immediately feasible, disabling remote management features and restricting access to trusted IP addresses can reduce exposure. 8) Regularly reviewing network logs for signs of exploitation attempts and maintaining incident response readiness.