CVE-2021-45551 in D6200
Summary
by MITRE • 12/26/2021
Certain NETGEAR devices are affected by command injection by an authenticated user. This affects D6200 before 1.1.00.40, D7000 before 1.0.1.78, R6020 before 1.0.0.42, R6080 before 1.0.0.42, R6050 before 1.0.1.26, JR6150 before 1.0.1.26, R6120 before 1.0.0.66, R6220 before 1.1.0.110, R6230 before 1.1.0.110, R6260 before 1.1.0.64, R6800 before 1.2.0.62, R6700v2 before 1.2.0.62, R6900v2 before 1.2.0.62, R7450 before 1.2.0.62, AC2100 before 1.2.0.62, AC2400 before 1.2.0.62, AC2600 before 1.2.0.62, and WNR2020 before 1.1.0.62.
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Analysis
by VulDB Data Team • 12/28/2021
This vulnerability represents a critical command injection flaw in NETGEAR networking equipment that allows authenticated users to execute arbitrary commands on affected devices. The issue stems from insufficient input validation and sanitization within the device's web interface and management protocols, creating a pathway for malicious actors who have already gained access to legitimate user credentials to escalate their privileges and compromise the entire network infrastructure. The vulnerability affects a wide range of NETGEAR routers and access points across multiple product lines, including popular models like the R6020, R6080, R6050, and various AC series devices, indicating a systemic flaw in the firmware implementation that requires immediate attention.
The technical implementation of this vulnerability falls under CWE-77, which specifically addresses command injection flaws where user-supplied data is directly incorporated into system commands without proper sanitization. Attackers can exploit this weakness by crafting malicious input through the device's web administration interface or API endpoints, potentially leading to complete system compromise. The flaw typically manifests when the device processes user input for network configuration parameters, diagnostic commands, or other administrative functions without adequate validation, allowing attackers to inject shell commands that execute with the privileges of the authenticated user. This particular vulnerability demonstrates how even authenticated access can be leveraged to gain unauthorized control over network infrastructure, making it particularly dangerous in enterprise environments where network devices often serve as critical attack vectors.
The operational impact of CVE-2021-45551 extends far beyond simple privilege escalation, as it can enable attackers to establish persistent backdoors, redirect network traffic, modify firewall rules, and potentially use the compromised devices as launching points for further attacks against internal networks. According to ATT&CK framework category T1059, this vulnerability facilitates command and scripting interpreter techniques, allowing attackers to execute code in the context of the affected system. The affected devices, being network infrastructure components, can provide attackers with unprecedented access to internal network segments, potentially enabling lateral movement, data exfiltration, and man-in-the-middle attacks. Organizations using these vulnerable devices face significant risk of network infiltration, as the compromised routers can serve as persistent footholds for attackers to maintain long-term access to otherwise secure network environments.
Mitigation strategies should include immediate firmware updates from NETGEAR addressing the command injection vulnerability, with particular attention to the specific version numbers mentioned in the CVE description. Network administrators must also implement additional security controls such as network segmentation, monitoring for unusual command execution patterns, and regular security assessments of network infrastructure devices. The vulnerability highlights the importance of maintaining up-to-date firmware across all network equipment and demonstrates why organizations should establish robust patch management processes that include network infrastructure components. Additionally, implementing network access controls and limiting administrative access to only trusted users can reduce the attack surface and minimize the potential impact of such vulnerabilities, as the flaw requires authenticated access to exploit, making proper access control and credential management essential defensive measures.