CVE-2024-39944 Overview
CVE-2024-39944 affects a wide range of Dahua network video recorder (NVR) and IP camera (IPC) products. Attackers can send crafted data packets to a vulnerable network interface and cause the device to crash. The flaw is exploitable remotely over the network without authentication or user interaction, and it impacts device availability. Dahua has published a security advisory and firmware updates for affected models, including the NVR4xxx-4KS2/L, NVR4xxx-4KS3, NVR4xxx-4KS2/I, IPC-HFS8849G-Z3-LED, and IPC-HFS8449G-Z7-LED product families.
Critical Impact
Unauthenticated remote attackers can crash Dahua NVR and IPC devices by sending malformed packets, disrupting video surveillance and recording operations.
Affected Products
- Dahua NVR4xxx-4KS2/L firmware (NVR4104, NVR4108, NVR4116, NVR4204, NVR4208, NVR4216, NVR4232 series)
- Dahua NVR4xxx-4KS3 firmware (NVR4104, NVR4108, NVR4116, NVR4204, NVR4208, NVR4216, NVR4232 series, including 960G variants)
- Dahua NVR4xxx-4KS2/I firmware (NVR4416, NVR4432, NVR4816, NVR4832 series) and IPC-HFS8849G-Z3-LED / IPC-HFS8449G-Z7-LED firmware
Discovery Timeline
- 2024-07-31 - CVE-2024-39944 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-39944
Vulnerability Analysis
The vulnerability is a network-reachable denial of service issue affecting Dahua NVR and IPC firmware. According to the vendor advisory, an attacker can transmit specially crafted data packets to a vulnerable service interface exposed by the device. Processing these malformed packets causes the device to crash, interrupting live video, recording, and management functions until the device is restarted. The associated weaknesses are tracked under [CWE-770] (Allocation of Resources Without Limits or Throttling) and [CWE-20] (Improper Input Validation), indicating that the affected interface fails to properly validate or constrain incoming data.
Root Cause
The root cause lies in insufficient input validation and resource handling within a network-facing service on the affected Dahua devices. The service does not adequately sanitize or bound the structure and size of incoming packets, allowing malformed input to trigger an unhandled error condition that terminates the responsible process. Because the impacted devices are embedded video surveillance appliances, a crash typically translates into loss of monitoring and recording until the device recovers.
Attack Vector
Exploitation requires only network access to the vulnerable service on the target device. No authentication and no user interaction are required. An attacker on the same network segment, or any network path that can reach the exposed Dahua management interface, can deliver crafted packets to cause the crash. Devices exposed to the internet are at higher risk, while internal exposure still permits insider or lateral-movement abuse. No public proof-of-concept or exploit code is currently listed for CVE-2024-39944, and it is not present on the CISA Known Exploited Vulnerabilities catalog.
No verified exploit code is publicly available for CVE-2024-39944. Refer to the Dahua Security Advisory for vendor-confirmed technical details and affected firmware builds.
Detection Methods for CVE-2024-39944
Indicators of Compromise
- Unexpected reboots or service restarts on Dahua NVR or IPC devices without corresponding administrative actions.
- Loss of recording continuity or gaps in video archives correlated with network activity targeting device management ports.
- Repeated TCP/UDP sessions from a single source toward Dahua device service ports immediately preceding device unavailability.
Detection Strategies
- Monitor network telemetry for anomalous packet patterns directed at Dahua NVR/IPC management interfaces, especially malformed protocol traffic.
- Correlate device-down events from the video management system (VMS) with firewall and IDS logs to identify packet-based crash patterns.
- Use network IDS signatures from your vendor for known Dahua protocol abuse and DoS attempts.
Monitoring Recommendations
- Track device uptime and health metrics from Dahua devices via SNMP or vendor APIs and alert on unscheduled restarts.
- Log and review inbound connections to ports exposed by Dahua devices, prioritizing devices reachable from untrusted networks.
- Centralize syslog and network flow data from camera VLANs into a SIEM for correlation and historical analysis.
How to Mitigate CVE-2024-39944
Immediate Actions Required
- Inventory all Dahua NVR and IPC devices in the listed product families and verify firmware versions against the vendor advisory.
- Apply the firmware updates published by Dahua for each affected model as soon as possible.
- Restrict network access to device management interfaces to trusted administrative networks only.
Patch Information
Dahua has issued firmware updates for the affected NVR and IPC models. Refer to the Dahua Security Advisory for the authoritative list of fixed firmware versions and download links. Apply the appropriate firmware update for each device model and verify the post-upgrade version against the advisory.
Workarounds
- Place Dahua devices behind a firewall and block inbound access from untrusted networks and the public internet.
- Segment surveillance devices into a dedicated VLAN with strict ACLs limiting which hosts can reach device service ports.
- Disable any unused network services on the device and require VPN access for remote administration until firmware is applied.
# Configuration example: restrict access to Dahua device management ports
# Replace 10.10.20.0/24 with your camera VLAN and 10.10.99.10 with the admin host
iptables -A FORWARD -s 10.10.99.10 -d 10.10.20.0/24 -p tcp --dport 37777 -j ACCEPT
iptables -A FORWARD -d 10.10.20.0/24 -p tcp --dport 37777 -j DROP
iptables -A FORWARD -d 10.10.20.0/24 -p tcp --dport 80 -j DROP
iptables -A FORWARD -d 10.10.20.0/24 -p tcp --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
