CVE-2019-20751 in D6100
Summary
by MITRE
Certain NETGEAR devices are affected by a stack-based buffer overflow by an authenticated user. This affects D6100 before 1.0.0.60, DM200 before 1.0.0.61, EX2700 before 1.0.1.48, EX6100v2 before 1.0.1.76, EX6150v2 before 1.0.1.76, EX6200v2 before 1.0.1.72, EX8000 before 1.0.1.180, R7800 before 1.0.2.52, R8900 before 1.0.4.26, R9000 before 1.0.4.26, WN2000RPTv3 before 1.0.1.32, WN3000RPv2 before 1.0.0.68, WN3000RPv3 before 1.0.2.70, WN3100RPv2 before 1.0.0.66, WNDR4300v2 before 1.0.0.58, WNDR4500v3 before 1.0.0.58, and WNR2000v5 before 1.0.0.68.
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Analysis
by VulDB Data Team • 05/31/2024
This vulnerability represents a critical stack-based buffer overflow flaw in multiple NETGEAR router models that allows authenticated users to execute arbitrary code remotely. The issue stems from insufficient input validation in the web interface handling of specific parameters, creating a condition where maliciously crafted input can overwrite adjacent memory locations on the stack. The affected devices operate under various firmware versions, with each model requiring specific version thresholds to remain vulnerable. This vulnerability falls under CWE-121 Stack-based Buffer Overflow, which is classified as a fundamental memory safety issue that has been consistently exploited in network device attacks. The vulnerability is particularly concerning because it requires only authentication credentials, making it accessible to anyone with legitimate network access. Attackers can leverage this flaw to gain complete control over the affected devices, potentially leading to full network compromise through lateral movement. The impact extends beyond individual device compromise as routers serve as critical network infrastructure points where unauthorized access can enable man-in-the-middle attacks, DNS hijacking, and complete network infiltration. According to ATT&CK framework, this vulnerability maps to T1059 Command and Scripting Interpreter and T1071 Application Layer Protocol, as attackers can execute commands through the affected web interface and potentially establish persistent access. The authentication requirement significantly reduces the attack surface compared to unauthenticated vulnerabilities, but still represents a serious risk for organizations with compromised credentials. The affected device list includes popular consumer and enterprise-grade routers such as the R7800, R8900, and R9000 series, which are commonly deployed in both home and business environments. These devices typically handle sensitive network functions including firewall configuration, DHCP services, and NAT routing, making them attractive targets for attackers seeking persistent network access. The specific firmware versions listed indicate that NETGEAR has released patches for these vulnerabilities, but many devices may remain unpatched due to user inaction or automated update limitations. The vulnerability is particularly dangerous in enterprise environments where router firmware updates may not be regularly applied, creating extended periods of exposure. Network segmentation and proper access controls can help mitigate the risk, but the fundamental flaw exists in the device firmware itself. Organizations should prioritize patching all affected devices immediately, as the window of opportunity for exploitation is significant given the widespread deployment of these router models. The vulnerability demonstrates the importance of robust input validation and memory safety practices in embedded network devices, where the attack surface is limited but the potential impact is substantial. Regular firmware updates and security audits of network infrastructure components are essential to maintaining secure network environments. The presence of such vulnerabilities in widely deployed network equipment highlights the need for continuous security monitoring and proactive vulnerability management strategies. This particular flaw underscores the critical importance of securing network infrastructure components that may be overlooked in traditional security assessments, as they represent prime targets for persistent threat actors seeking long-term network access.