CVE-2021-45542 in RAX200
Summary
by MITRE • 12/26/2021
Certain NETGEAR devices are affected by command injection by an authenticated user. This affects RAX200 before 1.0.4.120, RAX75 before 1.0.4.120, RAX80 before 1.0.4.120, RBK852 before 3.2.17.12, RBR850 before 3.2.17.12, and RBS850 before 3.2.17.12.
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Analysis
by VulDB Data Team • 12/28/2021
The vulnerability CVE-2021-45542 represents a critical command injection flaw affecting multiple NETGEAR wireless routers and access points within the RAX and RBK product lines. This vulnerability stems from insufficient input validation and sanitization in the affected devices' web-based management interfaces, allowing authenticated users to inject arbitrary commands that execute with elevated privileges. The flaw exists in firmware versions prior to the specified patches, with affected models including RAX200, RAX75, RAX80, RBK852, RBR850, and RBS850, all of which share a common software architecture that fails to properly handle user-supplied input in command execution contexts.
The technical implementation of this vulnerability involves the improper handling of user-provided parameters within the device's web management interface. When authenticated users submit specific input through web forms or API endpoints, the system fails to validate or sanitize these inputs before incorporating them into system commands. This creates a classic command injection scenario where malicious input can be interpreted by the underlying operating system shell, allowing attackers to execute arbitrary code on the device. The vulnerability is particularly dangerous because it requires only authentication, which is typically obtained through default credentials or previously compromised accounts, making it accessible to attackers who have gained initial access to the network.
From an operational perspective, this vulnerability presents a significant risk to network security infrastructure as it allows authenticated attackers to gain full control over affected devices. Once compromised, these routers can serve as pivot points for lateral movement within the network, potentially enabling attackers to access sensitive internal systems, intercept network traffic, or establish persistent backdoors. The impact extends beyond individual device compromise, as these devices often serve as network gateways, making them prime targets for attackers seeking to establish long-term access to entire network segments. The vulnerability also affects the device's ability to maintain network integrity and security policies, as attackers can modify routing tables, disable security features, or redirect network traffic.
The mitigation strategy for CVE-2021-45542 involves immediate firmware updates from NETGEAR addressing the command injection flaw. Organizations should prioritize updating all affected devices to the latest firmware versions, particularly focusing on the specified version numbers that contain the necessary patches. Additionally, network administrators should implement strict access controls for device management interfaces, including disabling default credentials, implementing strong authentication mechanisms, and restricting management access to trusted IP addresses. Security monitoring should be enhanced to detect unusual command execution patterns or unauthorized access attempts to device management interfaces, as outlined in the mitre ATT&CK framework under the T1059.001 technique for command and scripting interpreter. The vulnerability aligns with CWE-77 and CWE-88 categories, representing command injection flaws that lack proper input validation and sanitization in network device management interfaces, making it a critical concern for enterprise network security posture.