CVE-2025-11100 is a command injection vulnerability identified in the D-Link DIR-823X router firmware version 250416. The flaw exists in the uci_set function, which is invoked through the /goform/set_wifi_blacklists endpoint. This endpoint is responsible for managing Wi-Fi blacklist configurations but fails to properly sanitize user input, allowing attackers to inject and execute arbitrary system commands remotely. The vulnerability does not require user interaction or authentication, making it accessible to any remote attacker who can reach the router’s management interface. The CVSS 4.0 base score of 5.3 reflects a medium severity, considering the network attack vector, low complexity, no privileges required, and no user interaction, but limited impact on confidentiality, integrity, and availability. The exploit code is publicly available, increasing the risk of exploitation, although no active exploitation has been reported so far. The vulnerability could allow attackers to take control of the router, modify configurations, intercept or redirect traffic, or launch further attacks within the network. The lack of a patch link indicates that a firmware update may not yet be available, necessitating interim mitigations. The vulnerability affects a widely deployed consumer and small business router model, which is commonly used in European households and organizations, making it a relevant threat in that region.

For European organizations, exploitation of CVE-2025-11100 could lead to unauthorized remote control of network routers, compromising network perimeter security. Attackers could manipulate router settings, intercept or redirect network traffic, and potentially pivot to internal systems, risking data confidentiality and integrity. The availability of network services could also be disrupted by malicious commands, affecting business continuity. Small and medium enterprises relying on D-Link DIR-823X devices for internet connectivity or Wi-Fi management are particularly vulnerable. The public availability of exploit code increases the likelihood of opportunistic attacks, especially in environments with exposed or poorly secured router management interfaces. Given the router’s common use in home offices and small businesses, this vulnerability could also impact remote workers and distributed teams across Europe, complicating incident response. The medium severity rating suggests a moderate but tangible risk, emphasizing the need for timely mitigation to prevent escalation or lateral movement within networks.

1. Immediately restrict access to the router’s management interface by disabling remote administration or limiting it to trusted IP addresses. 2. Implement network segmentation to isolate routers from critical internal systems, reducing potential lateral movement. 3. Monitor network traffic and router logs for unusual commands or configuration changes indicative of exploitation attempts. 4. Apply any available firmware updates from D-Link as soon as they are released to address this vulnerability. 5. If patches are not yet available, consider temporary replacement of affected devices with models not impacted by this vulnerability. 6. Educate users and administrators about the risks of exposing router management interfaces to the internet. 7. Employ intrusion detection/prevention systems (IDS/IPS) tuned to detect exploitation attempts targeting /goform/set_wifi_blacklists or suspicious command injection patterns. 8. Regularly audit router configurations and firmware versions across the organization to ensure compliance with security policies.