CVE-2021-45538 in RAX75
Summary
by MITRE • 12/26/2021
Certain NETGEAR devices are affected by command injection by an authenticated user. This affects RAX75 before 1.0.3.106, RAX80 before 1.0.3.106, 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-2021-45538 represents a critical command injection flaw affecting multiple NETGEAR wireless routers and access points within the RAX and RBK/RBR/RBS series. This vulnerability stems from insufficient input validation and sanitization in the affected devices' web interface handling mechanisms. An authenticated attacker with access to the device's administrative interface can exploit this weakness to execute arbitrary commands on the underlying operating system. The affected firmware versions indicate a widespread issue across several product lines, suggesting a systemic flaw in the software development lifecycle or shared code components. This command injection vulnerability allows attackers to gain unauthorized control over device operations, potentially enabling them to modify network configurations, install malicious software, or establish persistent backdoors within the network infrastructure. The authentication requirement significantly reduces the attack surface compared to unauthenticated vulnerabilities, but it still represents a serious security risk for organizations relying on these devices for network management.
The technical exploitation of this vulnerability occurs through the manipulation of input parameters within the device's web administration interface. When an authenticated user submits malicious input to specific parameters, the system fails to properly validate or sanitize the data before processing it within the command execution context. This allows attackers to inject operating system commands that are then executed with the privileges of the web server process, typically running with elevated system permissions. The vulnerability aligns with CWE-77, which describes command injection flaws where user-supplied data is directly incorporated into command strings without proper sanitization. The impact extends beyond simple command execution to include potential privilege escalation and persistent access to the affected network devices, making it particularly dangerous for enterprise environments where these devices serve as network gateways and access points. Network security controls may be bypassed, and the compromised devices can serve as launching points for further attacks against internal network resources.
The operational impact of CVE-2021-45538 poses significant risks to network security and integrity across affected deployments. Organizations utilizing these NETGEAR devices may experience unauthorized access to their network infrastructure, potentially leading to data breaches, network disruption, or complete compromise of the affected access points. The vulnerability's presence in multiple device models within the same product line suggests that organizations may face widespread compromise if they have deployed several affected devices throughout their network infrastructure. Attackers could leverage this vulnerability to modify routing tables, disable network services, or establish persistent access points within the network. The authentication requirement does not eliminate the threat, as compromised user credentials or social engineering attacks could provide attackers with the necessary access to exploit this vulnerability. This vulnerability directly impacts the CIA triad by compromising confidentiality through unauthorized access to network information, integrity through potential modification of network configurations, and availability through possible service disruption. The attack pattern aligns with ATT&CK technique T1059.001 for command and scripting interpreter, specifically shell scripting, and T1068 for exploit for privilege escalation.
Organizations should immediately implement mitigations including firmware updates from NETGEAR to address the command injection vulnerability in affected devices. The recommended approach involves upgrading all impacted RAX and RBK/RBR/RBS series devices to firmware versions 1.0.3.106 or later for RAX devices and 3.2.16.6 or later for RBK/RBR/RBS devices. Network segmentation and access control measures should be enhanced to limit administrative access to these devices, ensuring that only authorized personnel can access the administrative interfaces. Regular monitoring of device logs for suspicious activity and implementing network intrusion detection systems can help identify potential exploitation attempts. Additionally, organizations should conduct thorough inventory assessments to identify all affected devices within their network infrastructure and prioritize remediation efforts accordingly. Security configuration reviews should be performed to ensure that default credentials are changed and unnecessary services are disabled. The vulnerability highlights the importance of maintaining up-to-date firmware and implementing robust network security practices to prevent unauthorized access to critical network infrastructure components.