CVE-2019-9677 in IPC-HDW1X2X
Summary
by MITRE
The specific fields of CGI interface of some Dahua products are not strictly verified, an attacker can cause a buffer overflow by constructing malicious packets. Affected products include: IPC-HDW1X2X,IPC-HFW1X2X,IPC-HDW2X2X,IPC-HFW2X2X,IPC-HDW4X2X,IPC-HFW4X2X,IPC-HDBW4X2X,IPC-HDW5X2X,IPC-HFW5X2X for versions which Build time is before August 18, 2019.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 08/30/2020
The vulnerability identified as CVE-2019-9677 represents a critical buffer overflow flaw within the Common Gateway Interface implementation of Dahua security devices, specifically affecting a range of network video cameras and recording systems. This weakness resides in the improper validation of input parameters within the CGI interface, which serves as a critical communication pathway between web servers and executable programs for handling user requests. The affected Dahua models including IPC-HDW1X2X, IPC-HFW1X2X, IPC-HDW2X2X, IPC-HFW2X2X, IPC-HDW4X2X, IPC-HFW4X2X, IPC-HDBW4X2X, IPC-HDW5X2X, and IPC-HFW5X2X all share this vulnerable implementation where input fields are not adequately sanitized or validated before processing. The vulnerability is particularly concerning as it affects devices with build times prior to August 18, 2019, indicating that manufacturers released firmware versions containing this flaw for extended periods without proper input validation mechanisms.
The technical exploitation of this vulnerability occurs through the construction of malicious packets that deliberately exceed the bounds of allocated memory buffers within the CGI processing routines. When these malformed packets are received by the affected Dahua devices, the insufficient input validation allows attackers to overwrite adjacent memory locations, potentially leading to arbitrary code execution or system crashes. This type of buffer overflow vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking permits data to be written beyond the allocated buffer space. The flaw demonstrates poor input validation practices in the CGI interface implementation, where attackers can manipulate parameter values to trigger memory corruption conditions that bypass normal execution flow and potentially provide unauthorized access to the device's underlying operating system.
The operational impact of this vulnerability extends beyond simple device disruption to potentially enable full system compromise of affected Dahua surveillance equipment. Network video cameras represent critical infrastructure components in security systems, and their compromise could allow attackers to gain unauthorized access to live video feeds, modify device configurations, or even establish persistent backdoors within network environments. The vulnerability affects devices that are commonly deployed in enterprise and industrial settings where security cameras serve as primary monitoring tools, making this a significant concern for organizations relying on Dahua products for physical security. Attackers could leverage this weakness to perform reconnaissance activities, capture sensitive video data, or use the compromised devices as entry points for broader network infiltration attempts. The vulnerability's exploitation potential aligns with ATT&CK technique T1219, which describes the use of legitimate remote services for persistence and lateral movement within compromised networks.
Organizations should immediately implement mitigations including firmware updates from Dahua that address the input validation deficiencies in the CGI interface implementation. The vendor released patches for affected devices that correct the buffer overflow conditions by implementing proper bounds checking and input validation mechanisms. Network segmentation and access control measures should be enforced to limit exposure of these devices to untrusted networks, while regular monitoring of device logs can help detect potential exploitation attempts. Security teams should also consider implementing intrusion detection systems capable of identifying malformed CGI requests that attempt to exploit this specific vulnerability. The vulnerability demonstrates the critical importance of proper input validation in network-facing applications and serves as a reminder of the need for regular security assessments of embedded systems and IoT devices that handle external network communications.