CVE-2021-45576 in RBK752
Summary
by MITRE • 12/26/2021
Certain NETGEAR devices are affected by command injection by an authenticated user. This affects RBK752 before 3.2.16.6, RBR750 before 3.2.16.6, RBS750 before 3.2.16.6, RBK852 before 3.2.16.6, RBR850 before 3.2.16.6, and RBS850 before 3.2.16.6.
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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 vulnerability specifically impacts a range of router and switch models including RBK752, RBR750, RBS750, RBK852, RBR850, and RBS850, all prior to firmware version 3.2.16.6. The issue stems from insufficient input validation and sanitization within the device management interfaces, creating a pathway for malicious command execution through crafted input parameters. This type of vulnerability falls under CWE-77 which categorizes command injection flaws as a serious security weakness that can lead to complete system compromise when exploited by authenticated attackers.
The technical implementation of this vulnerability occurs within the web-based management interfaces of these networking devices where user-supplied parameters are directly incorporated into system commands without proper sanitization. An authenticated user can manipulate input fields, particularly those related to network configuration, diagnostics, or logging functions, to inject malicious commands that get executed with the privileges of the web server process. This typically involves bypassing normal input validation mechanisms and exploiting the underlying shell command execution functions. The vulnerability is particularly concerning because it requires only authentication credentials to exploit, meaning that anyone with access to the device management interface can potentially compromise the entire network infrastructure.
The operational impact of this vulnerability extends far beyond simple unauthorized command execution, as it can enable complete network compromise and lateral movement within affected environments. An attacker with valid credentials could potentially gain root access to the device, modify network configurations, redirect traffic, establish backdoors, or use the compromised device as a pivot point for attacking other systems on the network. The affected devices serve as critical network infrastructure components, making them attractive targets for attackers seeking persistent access or to disrupt network operations. This vulnerability directly maps to ATT&CK technique T1059.001 for command and scripting interpreter and T1068 for exploit for privilege escalation, representing a significant threat to network security posture.
Mitigation strategies for this vulnerability primarily focus on immediate firmware updates to versions 3.2.16.6 or later, which address the input validation issues and command injection flaws. Network administrators should also implement strict access controls and monitor authentication logs for suspicious activity. Additional defensive measures include network segmentation to limit access to management interfaces, implementing strong authentication mechanisms, and regularly auditing device configurations. The vulnerability highlights the importance of proper input validation and secure coding practices in network device firmware development, aligning with security standards such as OWASP Top Ten and NIST cybersecurity frameworks. Organizations should conduct comprehensive vulnerability assessments to identify all affected devices within their network infrastructure and prioritize remediation efforts based on risk exposure and criticality of the impacted systems.