CVE-2021-45532 in R8000
Summary
by MITRE • 12/26/2021
NETGEAR R8000 devices before 1.0.4.76 are affected by command injection by an authenticated user.
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Analysis
by VulDB Data Team • 12/28/2021
The vulnerability identified as CVE-2021-45532 affects NETGEAR R8000 routers running firmware versions prior to 1.0.4.76, representing a critical command injection flaw that enables authenticated attackers to execute arbitrary commands on the affected devices. This vulnerability resides within the web-based management interface of the router, where user input is improperly validated and sanitized before being processed by the underlying system. The flaw allows an authenticated user to inject malicious commands that are subsequently executed with elevated privileges, potentially compromising the entire network infrastructure. The vulnerability is classified under CWE-77 as command injection, which is a well-known weakness in software applications where user-supplied data is directly incorporated into system commands without proper sanitization.
The technical exploitation of this vulnerability occurs through the web management interface of the router, where an authenticated user can manipulate input fields to inject malicious shell commands. The vulnerability specifically affects how the device processes certain parameters in HTTP requests, allowing attackers to bypass authentication checks and execute arbitrary code on the router's operating system. This creates a persistent threat vector where an attacker with legitimate network access can escalate privileges and gain full control over the device. The impact extends beyond simple command execution as it provides attackers with the ability to modify network configurations, intercept traffic, and potentially establish persistence mechanisms within the network.
From an operational standpoint, this vulnerability poses significant risks to enterprise and home network security, as it allows attackers who have gained legitimate access to the router's management interface to escalate their privileges and compromise the entire network infrastructure. The affected NETGEAR R8000 devices are commonly deployed in enterprise environments where they serve as critical network gateways, making this vulnerability particularly dangerous. The command injection flaw could enable attackers to redirect network traffic, install backdoors, or exfiltrate sensitive network information. According to ATT&CK framework, this vulnerability maps to T1059.001 (Command and Scripting Interpreter: PowerShell) and T1566 (Phishing) as attackers could use this to establish persistent access and further network infiltration. The vulnerability also aligns with T1071.004 (Application Layer Protocol: DNS) and T1021.001 (Remote Services: Remote Desktop Protocol) as attackers may use compromised routers to pivot to other network resources.
Mitigation strategies for CVE-2021-45532 primarily involve immediate firmware updates to version 1.0.4.76 or later, which contain patches addressing the command injection vulnerability. Network administrators should also implement additional security controls including disabling unnecessary web management interfaces, restricting access to router management functions through firewall rules, and implementing network segmentation to limit the potential impact of compromise. The vulnerability highlights the importance of regular security updates and proper input validation in network device firmware. Organizations should also consider implementing network monitoring solutions to detect anomalous command execution patterns and establish incident response procedures for device compromise. Security teams should conduct thorough vulnerability assessments to identify other potentially affected devices within their network infrastructure and ensure proper access controls are in place to limit the attack surface. Additionally, the vulnerability underscores the necessity of following secure coding practices and implementing proper input sanitization techniques to prevent similar issues in future deployments.