CVE-2018-21210 in D3600
Summary
by MITRE
Certain NETGEAR devices are affected by a buffer overflow by an unauthenticated attacker. This affects D3600 before 1.0.0.67, D6000 before 1.0.0.67, D7800 before 1.0.1.30, EX2700 before 1.0.1.28, R6100 before 1.0.1.20, R7500 before 1.0.0.118, R7500v2 before 1.0.3.24, R7800 before 1.0.2.40, R9000 before 1.0.2.52, WN2000RPTv3 before 1.0.1.20, WN3000RPv3 before 1.0.2.50, WN3100RPv2 before 1.0.0.56, WNDR3700v4 before 1.0.2.96, WNDR4300 before 1.0.2.98, WNDR4300v2 before 1.0.0.50, and WNDR4500v3 before 1.0.0.50.
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Analysis
by VulDB Data Team • 06/04/2024
This vulnerability represents a critical buffer overflow condition that affects multiple NETGEAR router models, creating a significant security risk for network infrastructure. The flaw exists in the web management interface of affected devices, where an unauthenticated attacker can exploit a buffer overflow through specially crafted input data. This vulnerability falls under the Common Weakness Enumeration category CWE-121, which describes heap-based buffer overflow conditions, and aligns with ATT&CK technique T1210 for exploitation of remote services. The affected models span various router families including D-series, R-series, and WN-series devices, indicating a widespread issue across NETGEAR's product portfolio. The vulnerability allows attackers to potentially execute arbitrary code on the affected devices, compromising the entire network infrastructure.
The technical implementation of this buffer overflow occurs when the device processes HTTP requests through its web interface without proper input validation. Attackers can send maliciously formatted data to specific endpoints, causing the application to write beyond the allocated buffer space and overwrite adjacent memory locations. This memory corruption can lead to unpredictable behavior including system crashes, denial of service conditions, or more critically, code execution. The vulnerability is particularly concerning because it requires no authentication, making it accessible to anyone on the network or even remotely if the device exposes the web interface to external traffic. The affected firmware versions indicate that this issue has persisted across multiple generations of devices, suggesting a fundamental flaw in the code implementation rather than a one-time coding error.
The operational impact of this vulnerability extends beyond simple network disruption to potentially enable complete system compromise and persistent network access. An attacker who successfully exploits this vulnerability could gain root access to the router, allowing them to modify network configurations, redirect traffic, install malware, or establish backdoors for continued access. The exposure of multiple router families means that organizations and individuals using these devices face significant risk, as the vulnerability affects both consumer-grade and enterprise-class networking equipment. This vulnerability particularly impacts the confidentiality, integrity, and availability of network services, as attackers could modify routing tables, disable security features, or create man-in-the-middle scenarios. The lack of authentication requirements makes this vulnerability especially dangerous in environments where routers are accessible from untrusted networks or have exposed web management interfaces.
Mitigation strategies should focus on immediate firmware updates from NETGEAR, which address the buffer overflow through proper input validation and memory management. Organizations should also implement network segmentation to isolate affected devices, disable unnecessary web management interfaces, and monitor network traffic for signs of exploitation attempts. Network administrators should consider implementing firewall rules to restrict access to router management interfaces to trusted IP addresses only, and regularly audit device configurations to ensure that management services are not exposed to unnecessary network segments. The vulnerability demonstrates the importance of secure coding practices and regular security assessments, as it reflects a failure to properly validate input data in web applications. Additionally, organizations should implement continuous monitoring solutions to detect anomalous network behavior that could indicate exploitation attempts, and maintain up-to-date vulnerability assessments to identify other potentially affected devices in their network infrastructure.