CVE-2019-20640 in D3600
Summary
by MITRE
Certain NETGEAR devices are affected by a stack-based buffer overflow by an unauthenticated attacker. This affects D3600 before 1.0.0.76, D6000 before 1.0.0.76, D6200 before 1.1.00.32, D7000 before 1.0.1.68, JR6150 before 1.0.1.18, PR2000 before 1.0.0.28, R6020 before 1.0.0.38, R6050 before 1.0.1.18, R6080 before 1.0.0.38, R6120 before 1.0.0.46, R6220 before 1.1.0.80, R6260 before 1.1.0.40, R6700v2 before 1.2.0.36, R6800 before 1.2.0.36, R6900v2 before 1.2.0.36, WNR2020 before 1.1.0.62, and XR500 before 2.3.2.32.
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Analysis
by VulDB Data Team • 05/26/2024
This vulnerability represents a critical stack-based buffer overflow condition that affects multiple NETGEAR router models, creating a significant security risk for network infrastructure. The flaw exists within the device's firmware implementation where insufficient input validation allows an attacker to craft malicious payloads that exceed the allocated stack buffer space. This type of vulnerability falls under CWE-121 Stack-based Buffer Overflow, which is classified as a serious weakness in software design that can lead to arbitrary code execution. The vulnerability impacts a wide range of NETGEAR devices including various DSL and cable modems, as well as wireless routers, making it particularly concerning for widespread deployment.
The technical exploitation of this vulnerability occurs through unauthenticated network requests, meaning that attackers do not require any credentials or prior access to the device to attempt exploitation. This characteristic significantly increases the attack surface and makes the vulnerability particularly dangerous as it can be exploited from outside the network perimeter. The buffer overflow condition typically occurs when user-supplied input is copied to a fixed-size buffer on the stack without proper bounds checking, allowing the overflow to overwrite adjacent memory locations including return addresses and function pointers. According to ATT&CK framework, this vulnerability maps to T1210 Exploitation of Remote Services, where attackers can leverage network-facing services to gain unauthorized access and potentially escalate privileges.
The operational impact of this vulnerability extends beyond simple unauthorized access, as successful exploitation can lead to complete device compromise and potential network infiltration. Attackers could leverage this vulnerability to execute arbitrary code on affected devices, potentially gaining persistent access to the network infrastructure, redirecting traffic, or establishing backdoors for future access. The affected device models span multiple generations and product lines, indicating a systemic issue in the firmware development process rather than isolated incidents. This vulnerability directly impacts network security posture by potentially allowing attackers to compromise network gateway devices that control traffic flow and provide essential connectivity services.
Mitigation strategies should focus on immediate firmware updates from NETGEAR to address the buffer overflow condition, as these updates typically include input validation fixes and stack protection mechanisms. Network administrators should also implement network segmentation to limit the potential impact of compromise and deploy intrusion detection systems to monitor for suspicious traffic patterns. Additionally, implementing network access controls and disabling unnecessary services can reduce the attack surface. The vulnerability demonstrates the importance of proper input validation and memory management practices in embedded systems, aligning with industry standards that emphasize secure coding practices. Organizations should conduct vulnerability assessments to identify all affected devices within their network infrastructure and prioritize remediation efforts based on risk exposure and network criticality.