CVE-2025-11100 is a command injection vulnerability identified in the D-Link DIR-823X router, specifically affecting firmware version 250416. The vulnerability resides in the uci_set function within the /goform/set_wifi_blacklists endpoint. This function is responsible for managing Wi-Fi blacklist settings, but due to improper input validation or sanitization, it allows an attacker to inject arbitrary commands. The vulnerability can be exploited remotely without requiring user interaction or authentication, as indicated by the CVSS vector (AV:N/AC:L/AT:N/UI:N/PR:L). The attack complexity is low, and the vulnerability impacts confidentiality, integrity, and availability to a limited extent. Although the CVSS score is 5.3 (medium severity), the presence of a publicly available exploit increases the risk of exploitation. The vulnerability allows attackers to execute arbitrary commands on the device, potentially leading to unauthorized control over the router, interception or manipulation of network traffic, or disruption of network services. No patches or official remediation links are currently provided, and no known exploits in the wild have been reported yet. However, the availability of a public exploit suggests that exploitation could become more widespread if not addressed promptly.

For European organizations, this vulnerability poses a significant risk, especially for those relying on the D-Link DIR-823X router model in their network infrastructure. Successful exploitation could lead to unauthorized access to internal networks, interception of sensitive communications, or disruption of network availability. This is particularly critical for small and medium enterprises (SMEs) and home office environments that may use this router model without advanced security monitoring. The compromise of routers can serve as a foothold for lateral movement within corporate networks or as a launchpad for further attacks such as data exfiltration or ransomware deployment. Additionally, compromised routers could be leveraged in botnet activities, impacting broader network stability. Given the remote and unauthenticated nature of the exploit, attackers can target vulnerable devices at scale, increasing the threat to European organizations that have not updated or secured their devices.

Organizations should immediately identify any D-Link DIR-823X devices running firmware version 250416 within their networks. Since no official patches are currently available, temporary mitigations include restricting remote access to router management interfaces, especially blocking access to the /goform/set_wifi_blacklists endpoint via firewall rules or access control lists. Network segmentation should be enforced to isolate vulnerable devices from critical systems. Monitoring network traffic for unusual command execution patterns or unexpected outbound connections from routers can help detect exploitation attempts. Organizations should also consider replacing affected devices with models that have received security updates or have better security track records. Regular firmware updates should be applied as soon as patches become available. Additionally, disabling remote management features unless absolutely necessary and enforcing strong administrative credentials can reduce the attack surface.