CVE-2019-9676 in IPC-HFW1XXX
Summary
by MITRE
Buffer overflow vulnerability found in some Dahua IP Camera devices IPC-HFW1XXX,IPC-HDW1XXX,IPC-HFW2XXX Build before 2018/11. The vulnerability exits in the function of redirection display for serial port printing information, which can not be used by product basic functions. After an attacker logs in locally, this vulnerability can be exploited to cause device restart or arbitrary code execution. Dahua has identified the corresponding security problems in the static code auditing process, so it has gradually deleted this function, which is no longer available in the newer devices and softwares. Dahua has released versions of the affected products to fix the vulnerability.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 10/05/2023
The CVE-2019-9676 vulnerability represents a critical buffer overflow flaw discovered in Dahua IP camera models including IPC-HFW1XXX, IPC-HDW1XXX, and IPC-HFW2XXX with firmware builds prior to November 2018. This vulnerability resides within the redirection display functionality for serial port printing information, a feature that was deemed non-essential for core product operations. The flaw manifests specifically in the handling of serial port data processing, where insufficient input validation and memory boundary checks create opportunities for malicious exploitation. The vulnerability's presence in the device's firmware represents a fundamental security weakness that bypasses normal operational controls and creates persistent attack vectors.
The technical exploitation of this buffer overflow occurs through local authentication access, requiring an attacker to first establish a valid login session with the device. Once authenticated, the attacker can craft malicious input data that exceeds the allocated buffer space within the serial port redirection function, causing memory corruption that can lead to device instability or complete system compromise. This vulnerability directly maps to CWE-121, which describes buffer overflow conditions where insufficient bounds checking allows attackers to overwrite adjacent memory locations. The exploitation mechanism aligns with ATT&CK technique T1059.007 for command and scripting interpreter, as successful exploitation could enable arbitrary code execution on the device. The buffer overflow's impact extends beyond simple memory corruption to potentially allow privilege escalation and persistent access to the compromised device.
The operational impact of this vulnerability poses significant risks to surveillance network security, particularly in environments where Dahua cameras are deployed for critical infrastructure monitoring. Device restarts caused by the buffer overflow can create denial of service conditions that compromise security monitoring capabilities, while arbitrary code execution enables full system compromise and potential lateral movement within networked environments. The vulnerability's persistence in older firmware versions means that organizations with legacy deployments face ongoing exposure risks, as the affected functionality was gradually removed from newer device releases through Dahua's static code auditing processes. This remediation approach demonstrates the vendor's recognition of the security implications and their subsequent efforts to eliminate the vulnerable code from future product iterations.
Organizations affected by this vulnerability should immediately implement firmware updates provided by Dahua to address the buffer overflow condition in their deployed camera systems. The mitigation strategy should include comprehensive inventory assessment to identify all affected devices and prioritization of remediation efforts based on network criticality and exposure levels. Network segmentation and access control measures should be enhanced to limit local authentication access points, while continuous monitoring of device behavior can help detect potential exploitation attempts. Security teams should also consider implementing intrusion detection systems that can identify anomalous serial port activity or unusual device restart patterns that may indicate exploitation attempts. The vulnerability's resolution through firmware updates represents a standard remediation approach that aligns with industry best practices for addressing buffer overflow vulnerabilities in embedded systems and IoT devices.