CVE-2021-45584 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
The vulnerability CVE-2021-45584 represents a critical command injection flaw affecting multiple NETGEAR router models including RBK752, RBR750, RBS750, RBK852, RBR850, and RBS850. This vulnerability exists within the web-based management interface of these devices and allows authenticated attackers to execute arbitrary commands on the affected systems. The flaw stems from insufficient input validation and sanitization within the device's command processing mechanisms, creating an avenue for malicious command injection attacks.
The technical implementation of this vulnerability involves the improper handling of user-supplied input within the device's web interface. When authenticated users submit specific command parameters through the management interface, the system fails to properly validate or sanitize these inputs before processing them. This allows an attacker who has already gained authentication credentials to inject malicious commands that are then executed with the privileges of the web server process. The vulnerability is classified under CWE-77 as "Command Injection" and aligns with ATT&CK technique T1059.001 for command and script injection.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it provides attackers with full control over the affected network devices. An authenticated attacker can execute arbitrary system commands, potentially gaining access to sensitive network information, modifying device configurations, or even establishing persistent backdoors. The affected firmware versions prior to 3.2.16.6 indicate that this was a widespread issue across multiple router models, suggesting a systemic flaw in the software implementation rather than isolated component issues.
The security implications of CVE-2021-45584 are particularly concerning given that these are network infrastructure devices that typically operate in sensitive environments. The vulnerability allows for complete device compromise, potentially enabling attackers to monitor network traffic, redirect traffic through malicious servers, or use the compromised devices as launch points for further attacks within the network. This aligns with ATT&CK tactic T1046 for network service scanning and T1071.004 for application layer protocol. Organizations should prioritize immediate remediation through firmware updates, as the vulnerability can be exploited by attackers who have already gained access to legitimate user credentials through various means including credential stuffing or phishing attacks.
The mitigation strategy involves applying the vendor-provided firmware updates to versions 3.2.16.6 and later, which contain proper input validation and sanitization measures. Network administrators should also implement additional security controls including monitoring for unusual command execution patterns, enforcing strong authentication mechanisms, and segmenting network access to limit potential attack surfaces. Regular security assessments of network infrastructure devices are essential to identify similar vulnerabilities that may exist in other network equipment. The vulnerability demonstrates the importance of proper input validation in web applications and highlights the need for comprehensive security testing throughout the software development lifecycle to prevent command injection vulnerabilities in network infrastructure devices.