CVE-2024-39944 is a high-severity vulnerability affecting Dahua IPC-HX8XXX series IP cameras and NVR4XXX series network video recorders with build times before February 2, 2024. The vulnerability is categorized under CWE-770, which involves allocation of resources without limits or throttling. Specifically, attackers can send specially crafted data packets to the vulnerable network interfaces of these devices, causing them to exhaust resources and crash, leading to a denial of service (DoS) condition. The CVSS v3.1 score is 7.5, reflecting a network attack vector with low attack complexity, no privileges required, and no user interaction needed. The impact is limited to availability, with no direct confidentiality or integrity compromise indicated. The lack of authentication and user interaction requirements means that any attacker with network access to these devices can exploit this vulnerability remotely. Although no known exploits are reported in the wild yet, the simplicity of the attack vector and the critical role these devices play in surveillance infrastructure make this a significant threat. Dahua devices are widely deployed in enterprise, public safety, and critical infrastructure environments, where availability of video feeds and recording is essential for security operations. The vulnerability stems from improper handling of incoming data packets, where resource allocation is not properly limited or throttled, allowing attackers to overwhelm the device's processing or memory resources, causing crashes or reboots. This can disrupt surveillance operations, potentially creating blind spots and increasing security risks.

For European organizations, the impact of CVE-2024-39944 can be substantial, especially for those relying on Dahua IPC-HX8XXX cameras and NVR4XXX recorders for physical security monitoring. A successful exploitation results in denial of service, causing devices to crash and become unavailable. This disrupts real-time video surveillance and recording, which can hinder incident detection, response, and forensic investigations. Critical infrastructure sectors such as transportation, energy, government facilities, and large enterprises that deploy these devices may face increased security risks due to loss of visibility. Additionally, prolonged outages could lead to regulatory compliance issues related to security monitoring and data retention. The remote and unauthenticated nature of the exploit increases the attack surface, especially for devices exposed to untrusted networks or insufficiently segmented internal networks. Given the growing reliance on video surveillance for security and operational intelligence, this vulnerability could be leveraged by threat actors to create windows of opportunity for physical or cyber attacks by disabling surveillance capabilities.

1. Immediate identification and inventory of all Dahua IPC-HX8XXX and NVR4XXX devices with build dates prior to February 2, 2024, is critical. 2. Apply vendor-provided patches or firmware updates as soon as they become available. Since no patch links are currently provided, organizations should monitor Dahua’s official channels for updates. 3. Implement network segmentation and access controls to restrict network access to these devices only to trusted management and monitoring systems, minimizing exposure to untrusted networks. 4. Deploy network-level protections such as intrusion detection/prevention systems (IDS/IPS) configured to detect and block anomalous or malformed packets targeting these devices. 5. Use rate limiting or traffic shaping on network segments hosting these devices to mitigate resource exhaustion attempts. 6. Monitor device logs and network traffic for signs of repeated crashes or unusual packet patterns indicative of exploitation attempts. 7. Consider temporary compensating controls such as disabling remote management interfaces exposed to the internet until patches are applied. 8. Engage with Dahua support for guidance and to obtain early access to firmware updates addressing this vulnerability. 9. Incorporate this vulnerability into incident response and business continuity planning to quickly restore surveillance capabilities if disruption occurs.