CVE-2019-20657 in D6200
Summary
by MITRE
Certain NETGEAR devices are affected by a buffer overflow by an authenticated user. This affects D6200 before 1.1.00.36, D7000 before 1.0.1.74, PR2000 before 1.0.0.28, R6020 before 1.0.0.42, R6080 before 1.0.0.42, R6050 before 1.0.1.24, JR6150 before 1.0.1.24, R6120 before 1.0.0.48, R6220 before 1.1.0.86, R6230 before 1.1.0.86, R6260 before 1.1.0.64, R6700v2 before 1.2.0.62, R6800 before 1.2.0.62, R6900v2 before 1.2.0.62, and WNR2020 before 1.1.0.62.
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Analysis
by VulDB Data Team • 05/26/2024
This vulnerability represents a critical buffer overflow condition that affects multiple NETGEAR router models, specifically those listed in the affected versions. The flaw exists within the web-based management interface of these devices, where an authenticated user can exploit a memory corruption issue through crafted input parameters. The vulnerability stems from insufficient input validation mechanisms within the device's firmware, allowing maliciously constructed data to overwrite adjacent memory locations beyond the intended buffer boundaries. This type of vulnerability falls under the common weakness enumeration CWE-121, which describes stack-based buffer overflow conditions, though the specific implementation in these routers may involve heap-based overflow scenarios given the nature of web interface processing. The affected devices operate with a web server component that processes user-supplied parameters without adequate bounds checking, creating an exploitable condition that can be leveraged by attackers who have already established authentication credentials.
The operational impact of this vulnerability extends beyond simple memory corruption, as it provides a potential pathway for privilege escalation and arbitrary code execution within the device's operating environment. An authenticated attacker with access to the device's web management interface can craft specific HTTP requests containing oversized input data that triggers the buffer overflow condition. This condition can result in the device crashing or potentially allow the execution of malicious code with the privileges of the web server process. The attack vector requires network access and valid user credentials, making it less severe than a remote code execution vulnerability but still highly concerning given the potential for persistent access to network infrastructure. The vulnerability affects a broad range of consumer and small office networking equipment, including various models of routers and wireless access points, creating widespread exposure across multiple device families.
Security implications of this vulnerability align with the ATT&CK framework's privilege escalation and persistence tactics, as the authenticated nature of the attack means that an attacker who gains initial access through other means could leverage this flaw to maintain control over the device. The buffer overflow could potentially be used to overwrite critical program variables, function pointers, or even execute shellcode within the device's memory space. Organizations and individuals using these affected NETGEAR devices face significant risk, as compromised routers can serve as persistent footholds for network reconnaissance, traffic interception, or as launching points for attacks against other devices on the local network. The vulnerability also impacts the device's overall reliability, as successful exploitation could cause denial of service conditions or unexpected device behavior. The affected firmware versions span multiple release cycles, indicating that this was not a newly introduced flaw but rather a long-standing issue that was not properly addressed through standard security updates.
Mitigation strategies for this vulnerability primarily involve applying the official firmware updates provided by NETGEAR, which address the specific buffer overflow conditions through proper input validation and memory management controls. System administrators should immediately implement firmware upgrades across all affected device models, particularly in environments where network security is paramount. Network segmentation and access control measures should be enhanced to limit the potential impact of a compromised device, including implementing strong authentication mechanisms and restricting administrative access to only necessary personnel. Regular vulnerability scanning and firmware inventory management should be established to identify and remediate similar issues across the network infrastructure. The vulnerability also underscores the importance of maintaining current firmware versions and implementing network monitoring to detect anomalous behavior that might indicate exploitation attempts. Organizations should consider implementing network access control lists and disabling unnecessary services on affected devices to reduce the attack surface and limit potential exploitation pathways.