CVE-2019-20731 in D6220
Summary
by MITRE
Certain NETGEAR devices are affected by a buffer overflow by an authenticated user. This affects D6220 before 1.0.0.40, D6400 before 1.0.0.74, D7000v2 before 1.0.0.74, D8500 before 1.0.3.39, EX3700 before 1.0.0.70, EX3800 before 1.0.0.70, EX6000 before 1.0.0.30, EX6100 before 1.0.2.22, EX6120 before 1.0.0.40, EX6130 before 1.0.0.22, EX6150v1 before 1.0.0.42, EX6200 before 1.0.3.88, EX7000 before 1.0.0.66, R6250 before 1.0.4.20, R6300v2 before 1.0.4.18, R6400v2 before 1.0.2.52, R6700 before 1.0.1.44, R6900 before 1.0.1.46, R7000 before 1.0.9.26, R6900P before 1.3.0.20, R7000P before 1.3.0.20, R7100LG before 1.0.0.34, R7300DST before 1.0.0.62, R8000 before 1.0.4.12, R7900P before 1.3.0.10, R8000P before 1.3.0.10, R8300 before 1.0.2.116, R8500 before 1.0.2.116, WN2500RPv2 before 1.0.1.54, and WNDR3400v3 before 1.0.1.18.
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Analysis
by VulDB Data Team • 05/31/2024
This vulnerability represents a critical buffer overflow condition affecting multiple NETGEAR router models that can be exploited by authenticated users within the device's administrative interface. The flaw manifests when the device processes user-supplied input without proper bounds checking, creating an opportunity for arbitrary code execution or system compromise. The affected devices span several product lines including the D-series, EX-series, R-series, and various other router models, indicating a widespread issue that impacts the overall security posture of these networking devices. The vulnerability specifically affects firmware versions prior to the listed patches, suggesting that manufacturers identified and addressed the issue through software updates.
The technical implementation of this buffer overflow stems from inadequate input validation mechanisms within the web-based management interface of these devices. When an authenticated user submits specially crafted data through administrative forms or API endpoints, the system fails to properly validate the input length, allowing malicious data to overwrite adjacent memory regions. This memory corruption can potentially lead to stack smashing, heap corruption, or other memory-related vulnerabilities that may be exploited to gain unauthorized access to the device's operating system. The vulnerability operates at the application layer and requires authentication, meaning an attacker must first obtain valid administrative credentials before attempting exploitation.
From an operational impact perspective, this vulnerability creates significant security risks for organizations and consumers who rely on these networking devices for their infrastructure. The authenticated nature of the attack means that an attacker who has already gained administrative access to the device can leverage this flaw to escalate privileges or execute arbitrary commands on the device itself. This could result in complete device compromise, allowing attackers to modify network configurations, intercept traffic, or use the device as a pivot point for attacking other systems within the network. The widespread affected product range suggests that many users may be exposed to this vulnerability, particularly those who have not applied the necessary firmware updates.
The mitigation strategy for this vulnerability involves immediate firmware updates from NETGEAR, as these patches typically include proper input validation and bounds checking mechanisms to prevent the buffer overflow condition. Network administrators should prioritize applying these updates across all affected devices in their infrastructure, especially those with administrative access to the affected routers. Additionally, organizations should implement network segmentation and access controls to limit the potential impact of such vulnerabilities, ensuring that administrative interfaces are not directly accessible from untrusted networks. Security monitoring should also be enhanced to detect any suspicious administrative activities that might indicate exploitation attempts. This vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and represents a common attack vector that can be addressed through proper input validation and secure coding practices. The ATT&CK framework categorizes this as a privilege escalation technique, where an authenticated user leverages a software vulnerability to gain higher-level system access, potentially leading to full network compromise.