CVE-2024-57684 is an access control vulnerability identified in the formDMZ.cgi component of the D-Link 816A2 router firmware version 1.10CNB05_R1B011D88210. The flaw arises because the device does not properly restrict access to the DMZ configuration interface, allowing unauthenticated attackers to send specially crafted POST requests to alter the DMZ settings. The DMZ (Demilitarized Zone) service typically exposes an internal host to external networks, bypassing firewall protections. By manipulating this setting, an attacker can redirect incoming traffic to a chosen internal IP address, effectively exposing that device to the internet and potentially enabling further exploitation or data exfiltration. The vulnerability is classified under CWE-276 (Incorrect Default Permissions) and has a CVSS v3.1 base score of 9.8, reflecting its critical severity. The attack vector is network-based with no privileges or user interaction required, making it highly exploitable. Although no patches or official fixes have been released yet, the vulnerability’s existence poses a significant risk to affected devices. The lack of authentication enforcement on this sensitive configuration interface is the root cause, highlighting a serious design flaw in the device’s firmware security model.

The impact of CVE-2024-57684 is severe for organizations using the affected D-Link 816A2 routers. By allowing unauthenticated attackers to modify DMZ settings, the vulnerability can expose internal network devices to direct internet access, bypassing firewall protections and network segmentation. This exposure can lead to unauthorized access, data theft, malware infection, lateral movement within the network, and potential full compromise of internal systems. Confidentiality, integrity, and availability of internal resources are all at risk. The ease of exploitation without authentication or user interaction increases the likelihood of widespread attacks once exploit code becomes available. Organizations relying on these routers for perimeter security or home office connectivity may face increased risk of intrusion and data breaches. The absence of patches exacerbates the threat, requiring immediate mitigation to prevent exploitation.

To mitigate CVE-2024-57684, organizations should first identify all devices running the affected D-Link 816A2 firmware version 1.10CNB05_R1B011D88210. Until an official patch is released, administrators should disable the DMZ feature entirely if not required, as this reduces the attack surface. Network segmentation and strict firewall rules should be applied to limit access to router management interfaces from untrusted networks. If remote management is enabled, it should be disabled or restricted to trusted IP addresses only. Monitoring network traffic for unusual POST requests targeting formDMZ.cgi can help detect exploitation attempts. Additionally, consider replacing affected devices with models that have updated firmware or better security controls. Vendors and users should prioritize firmware updates once available. Employing intrusion detection/prevention systems (IDS/IPS) with signatures targeting this vulnerability can provide additional defense layers.